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Sample records for nanoparticle pet-ct imaging

  1. Multi-modality PET-CT imaging of breast cancer in an animal model using nanoparticle x-ray contrast agent and 18F-FDG

    NASA Astrophysics Data System (ADS)

    Badea, C. T.; Ghaghada, K.; Espinosa, G.; Strong, L.; Annapragada, A.

    2011-03-01

    Multi-modality PET-CT imaging is playing an important role in the field of oncology. While PET imaging facilitates functional interrogation of tumor status, the use of CT imaging is primarily limited to anatomical reference. In an attempt to extract comprehensive information about tumor cells and its microenvironment, we used a nanoparticle xray contrast agent to image tumor vasculature and vessel 'leakiness' and 18F-FDG to investigate the metabolic status of tumor cells. In vivo PET/CT studies were performed in mice implanted with 4T1 mammary breast cancer cells.Early-phase micro-CT imaging enabled visualization 3D vascular architecture of the tumors whereas delayedphase micro-CT demonstrated highly permeable vessels as evident by nanoparticle accumulation within the tumor. Both imaging modalities demonstrated the presence of a necrotic core as indicated by a hypo-enhanced region in the center of the tumor. At early time-points, the CT-derived fractional blood volume did not correlate with 18F-FDG uptake. At delayed time-points, the tumor enhancement in 18F-FDG micro-PET images correlated with the delayed signal enhanced due to nanoparticle extravasation seen in CT images. The proposed hybrid imaging approach could be used to better understand tumor angiogenesis and to be the basis for monitoring and evaluating anti-angiogenic and nano-chemotherapies.

  2. Thoracic cancer imaging with PET/CT in radiation oncology

    NASA Astrophysics Data System (ADS)

    Chi, Pai-Chun Melinda

    Significance. Respiratory motion has been shown to cause artifacts in PET/CT imaging. This breathing artifact can have a significant impact on PET quantification and it can lead to large uncertainties when using PET for radiation therapy planning. We have demonstrated a promising solution to resolve the breathing artifact by acquiring respiration-averaged CT (ACT) for PET/CT. The purpose of this work was to optimize the ACT acquisition for clinical implementation and to evaluate the impact of ACT on PET/CT quantification. The hypothesis was that ACT is an effective method in removing the breathing artifact when compared to our current clinical protocol. Methods. Phase and cine approaches for acquiring ACT were investigated and the results of these two approaches were compared to the ACT generated from clinical 4DCT data sets (abbreviated as ACT10phs ). In the phase approach, ACT was generated based on combinations of selected respiratory phases; in the cine approach, ACT was generated based on cine images acquired over a fixed cine duration. The phase combination and cine duration that best approximated the ACT10phs were determined to be the optimized scanning parameters. 216 thoracic PET/CT patients were scanned with both current clinical and the ACT protocols. The effects of ACT on PET/CT quantification were assessed by comparing clinical PET/CT and ACT PET/CT using 3 metrics: PET/CT image alignment, maximum standardized uptake value (SUVmax), and threshold segmented gross tumor volume (GTV). Results. ACT10phs can be best approximated to within 2% of SUV variation by phase averaging based on 4 representative phases, and to within 3% by cine image averaging based on >3s of cine duration. We implemented the cine approach on the PET/CT scanners and acquired 216 patient data sets. 68% of patients had breathing artifacts in their clinical PET/CT and the artifacts were removed/reduced in all corresponding ACT PET/CT. PET/CT quantification for lesions <50 cm3 and

  3. PET/CT imaging in lung cancer: indications and findings*

    PubMed Central

    Hochhegger, Bruno; Alves, Giordano Rafael Tronco; Irion, Klaus Loureiro; Fritscher, Carlos Cezar; Fritscher, Leandro Genehr; Concatto, Natália Henz; Marchiori, Edson

    2015-01-01

    The use of PET/CT imaging in the work-up and management of patients with lung cancer has greatly increased in recent decades. The ability to combine functional and anatomical information has equipped PET/CT to look into various aspects of lung cancer, allowing more precise disease staging and providing useful data during the characterization of indeterminate pulmonary nodules. In addition, the accuracy of PET/CT has been shown to be greater than is that of conventional modalities in some scenarios, making PET/CT a valuable noninvasive method for the investigation of lung cancer. However, the interpretation of PET/CT findings presents numerous pitfalls and potential confounders. Therefore, it is imperative for pulmonologists and radiologists to familiarize themselves with the most relevant indications for and limitations of PET/CT, seeking to protect their patients from unnecessary radiation exposure and inappropriate treatment. This review article aimed to summarize the basic principles, indications, cancer staging considerations, and future applications related to the use of PET/CT in lung cancer. PMID:26176525

  4. PET/CT for radiotherapy: image acquisition and data processing.

    PubMed

    Bettinardi, V; Picchio, M; Di Muzio, N; Gianolli, L; Messa, C; Gilardi, M C

    2010-10-01

    This paper focuses on acquisition and processing methods in positron emission tomography/computed tomography (PET/CT) for radiotherapy (RT) applications. The recent technological evolutions of PET/CT systems are described. Particular emphasis is dedicated to the tools needed for the patient positioning and immobilization, to be used in PET/CT studies as well as during RT treatment sessions. The effect of organ and lesion motion due to patient's respiration on PET/CT imaging is discussed. Breathing protocols proposed to minimize PET/CT spatial mismatches in relation to respiratory movements are illustrated. The respiratory gated (RG) 4D-PET/CT techniques, developed to measure and compensate for organ and lesion motion, are then introduced. Finally a description is provided of different acquisition and data processing techniques, implemented with the aim at improving: i) image quality and quantitative accuracy of PET images, and ii) target volume definition and treatment planning in RT, by using specific and personalised motion information.

  5. Body-wide anatomy recognition in PET/CT images

    NASA Astrophysics Data System (ADS)

    Wang, Huiqian; Udupa, Jayaram K.; Odhner, Dewey; Tong, Yubing; Zhao, Liming; Torigian, Drew A.

    2015-03-01

    With the rapid growth of positron emission tomography/computed tomography (PET/CT)-based medical applications, body-wide anatomy recognition on whole-body PET/CT images becomes crucial for quantifying body-wide disease burden. This, however, is a challenging problem and seldom studied due to unclear anatomy reference frame and low spatial resolution of PET images as well as low contrast and spatial resolution of the associated low-dose CT images. We previously developed an automatic anatomy recognition (AAR) system [15] whose applicability was demonstrated on diagnostic computed tomography (CT) and magnetic resonance (MR) images in different body regions on 35 objects. The aim of the present work is to investigate strategies for adapting the previous AAR system to low-dose CT and PET images toward automated body-wide disease quantification. Our adaptation of the previous AAR methodology to PET/CT images in this paper focuses on 16 objects in three body regions - thorax, abdomen, and pelvis - and consists of the following steps: collecting whole-body PET/CT images from existing patient image databases, delineating all objects in these images, modifying the previous hierarchical models built from diagnostic CT images to account for differences in appearance in low-dose CT and PET images, automatically locating objects in these images following object hierarchy, and evaluating performance. Our preliminary evaluations indicate that the performance of the AAR approach on low-dose CT images achieves object localization accuracy within about 2 voxels, which is comparable to the accuracies achieved on diagnostic contrast-enhanced CT images. Object recognition on low-dose CT images from PET/CT examinations without requiring diagnostic contrast-enhanced CT seems feasible.

  6. Validating and improving CT ventilation imaging by correlating with ventilation 4D-PET/CT using {sup 68}Ga-labeled nanoparticles

    SciTech Connect

    Kipritidis, John Keall, Paul J.; Siva, Shankar; Hofman, Michael S.; Callahan, Jason; Hicks, Rodney J.

    2014-01-15

    Purpose: CT ventilation imaging is a novel functional lung imaging modality based on deformable image registration. The authors present the first validation study of CT ventilation using positron emission tomography with{sup 68}Ga-labeled nanoparticles (PET-Galligas). The authors quantify this agreement for different CT ventilation metrics and PET reconstruction parameters. Methods: PET-Galligas ventilation scans were acquired for 12 lung cancer patients using a four-dimensional (4D) PET/CT scanner. CT ventilation images were then produced by applying B-spline deformable image registration between the respiratory correlated phases of the 4D-CT. The authors test four ventilation metrics, two existing and two modified. The two existing metrics model mechanical ventilation (alveolar air-flow) based on Hounsfield unit (HU) change (V{sub HU}) or Jacobian determinant of deformation (V{sub Jac}). The two modified metrics incorporate a voxel-wise tissue-density scaling (ρV{sub HU} and ρV{sub Jac}) and were hypothesized to better model the physiological ventilation. In order to assess the impact of PET image quality, comparisons were performed using both standard and respiratory-gated PET images with the former exhibiting better signal. Different median filtering kernels (σ{sub m} = 0 or 3 mm) were also applied to all images. As in previous studies, similarity metrics included the Spearman correlation coefficient r within the segmented lung volumes, and Dice coefficient d{sub 20} for the (0 − 20)th functional percentile volumes. Results: The best agreement between CT and PET ventilation was obtained comparing standard PET images to the density-scaled HU metric (ρV{sub HU}) with σ{sub m} = 3 mm. This leads to correlation values in the ranges 0.22 ⩽ r ⩽ 0.76 and 0.38 ⩽ d{sub 20} ⩽ 0.68, with r{sup ¯}=0.42±0.16 and d{sup ¯}{sub 20}=0.52±0.09 averaged over the 12 patients. Compared to Jacobian-based metrics, HU-based metrics lead to statistically significant

  7. Nonrigid Image Registration for Head and Neck Cancer Radiotherapy Treatment Planning With PET/CT

    SciTech Connect

    Ireland, Rob H. . E-mail: r.ireland@sheffield.ac.uk; Dyker, Karen E.; Barber, David C.; Wood, Steven M.; Hanney, Michael B.; Tindale, Wendy B.; Woodhouse, Neil; Hoggard, Nigel; Conway, John; Robinson, Martin H.

    2007-07-01

    Purpose: Head and neck radiotherapy planning with positron emission tomography/computed tomography (PET/CT) requires the images to be reliably registered with treatment planning CT. Acquiring PET/CT in treatment position is problematic, and in practice for some patients it may be beneficial to use diagnostic PET/CT for radiotherapy planning. Therefore, the aim of this study was first to quantify the image registration accuracy of PET/CT to radiotherapy CT and, second, to assess whether PET/CT acquired in diagnostic position can be registered to planning CT. Methods and Materials: Positron emission tomography/CT acquired in diagnostic and treatment position for five patients with head and neck cancer was registered to radiotherapy planning CT using both rigid and nonrigid image registration. The root mean squared error for each method was calculated from a set of anatomic landmarks marked by four independent observers. Results: Nonrigid and rigid registration errors for treatment position PET/CT to planning CT were 2.77 {+-} 0.80 mm and 4.96 {+-} 2.38 mm, respectively, p = 0.001. Applying the nonrigid registration to diagnostic position PET/CT produced a more accurate match to the planning CT than rigid registration of treatment position PET/CT (3.20 {+-} 1.22 mm and 4.96 {+-} 2.38 mm, respectively, p = 0.012). Conclusions: Nonrigid registration provides a more accurate registration of head and neck PET/CT to treatment planning CT than rigid registration. In addition, nonrigid registration of PET/CT acquired with patients in a standardized, diagnostic position can provide images registered to planning CT with greater accuracy than a rigid registration of PET/CT images acquired in treatment position. This may allow greater flexibility in the timing of PET/CT for head and neck cancer patients due to undergo radiotherapy.

  8. MULTIMODALITY IMAGING: BEYOND PET/CT AND SPECT/CT

    PubMed Central

    Cherry, Simon R.

    2009-01-01

    Multimodality imaging with PET/CT and SPECT/CT has become commonplace in clinical practice and in preclinical and basic medical research. Do other combinations of imaging modalities have a similar potential to impact medical science and clinical medicine? The combination of PET or SPECT with MRI is an area of active research at the present time, while other, perhaps less obvious combinations, including CT/MR and PET/optical also are being studied. In addition to the integration of the instrumentation, there are parallel developments in synthesizing imaging agents that can be viewed by multiple imaging modalities. Is the fusion of PET and SPECT with CT the ultimate answer in multimodality imaging, or is it just the first example of a more general trend towards harnessing the complementary nature of the different modalities on integrated imaging platforms? PMID:19646559

  9. Gallium-68 EDTA PET/CT for Renal Imaging.

    PubMed

    Hofman, Michael S; Hicks, Rodney J

    2016-09-01

    Nuclear medicine renal imaging provides important functional data to assist in the diagnosis and management of patients with a variety of renal disorders. Physiologically stable metal chelates like ethylenediaminetetraacetic acid (EDTA) and diethylenetriamine penta-acetate (DTPA) are excreted by glomerular filtration and have been radiolabelled with a variety of isotopes for imaging glomerular filtration and quantitative assessment of glomerular filtration rate. Gallium-68 ((68)Ga) EDTA PET usage predates Technetium-99m ((99m)Tc) renal imaging, but virtually disappeared with the widespread adoption of gamma camera technology that was not optimal for imaging positron decay. There is now a reemergence of interest in (68)Ga owing to the greater availability of PET technology and use of (68)Ga to label other radiotracers. (68)Ga EDTA can be used a substitute for (99m)Tc DTPA for wide variety of clinical indications. A key advantage of PET for renal imaging over conventional scintigraphy is 3-dimensional dynamic imaging, which is particularly helpful in patients with complex anatomy in whom planar imaging may be nondiagnostic or difficult to interpret owing to overlying structures containing radioactive urine that cannot be differentiated. Other advantages include accurate and absolute (rather than relative) camera-based quantification, superior spatial and temporal resolution and integrated multislice CT providing anatomical correlation. Furthermore, the (68)Ga generator enables on-demand production at low cost, with no additional patient radiation exposure compared with conventional scintigraphy. Over the past decade, we have employed (68)Ga EDTA PET/CT primarily to answer difficult clinical questions in patients in whom other modalities have failed, particularly when it was envisaged that dynamic 3D imaging would be of assistance. We have also used it as a substitute for (99m)Tc DTPA if unavailable owing to supply issues, and have additionally examined the role of

  10. Pixel-feature hybrid fusion for PET/CT images.

    PubMed

    Zhu, Yang-Ming; Nortmann, Charles A

    2011-02-01

    Color blending is a popular display method for functional and anatomic image fusion. The underlay image is typically displayed in grayscale, and the overlay image is displayed in pseudo colors. This pixel-level fusion provides too much information for reviewers to analyze quickly and effectively and clutters the display. To improve the fusion image reviewing speed and reduce the information clutter, a pixel-feature hybrid fusion method is proposed and tested for PET/CT images. Segments of the colormap are selectively masked to have a few discrete colors, and pixels displayed in the masked colors are made transparent. The colormap thus creates a false contouring effect on overlay images and allows the underlay to show through to give contours an anatomic context. The PET standardized uptake value (SUV) is used to control where colormap segments are masked. Examples show that SUV features can be extracted and blended with CT image instantaneously for viewing and diagnosis, and the non-feature part of the PET image is transparent. The proposed pixel-feature hybrid fusion highlights PET SUV features on CT images and reduces display clutters. It is easy to implement and can be used as complementarily to existing pixel-level fusion methods.

  11. 68Ga-PSMA PET/CT Imaging in Multiple Myeloma.

    PubMed

    Sasikumar, Arun; Joy, Ajith; Pillai, M R A; Nanabala, Raviteja; Thomas, Boben

    2017-02-01

    The potential applications of Ga-labeled prostate-specific membrane antigen (PSMA) PET/CT in the imaging of prostate cancer are now well established. A few case reports regarding the potential use of Ga-PSMA PET/CT in nonprostate cancer malignancies are also published. Apparently, the tumor neoangiogenesis is the mechanism attributed to increased Ga-PSMA uptake in the tumor sites in nonprostatic malignancies. We describe the use of Ga-PSMA PET/CT in imaging multiple myeloma. The intense Ga-PSMA avidity of the lesions also opens up the possibility of theranostics with Lu-PSMA.

  12. Posttreatment PET/CT Rather Than Interim PET/CT Using Deauville Criteria Predicts Outcome in Pediatric Hodgkin Lymphoma: A Prospective Study Comparing PET/CT with Conventional Imaging.

    PubMed

    Bakhshi, Sameer; Bhethanabhotla, Sainath; Kumar, Rakesh; Agarwal, Krishankant; Sharma, Punit; Thulkar, Sanjay; Malhotra, Arun; Dhawan, Deepa; Vishnubhatla, Sreenivas

    2017-04-01

    Data about the significance of (18)F-FDG PET at interim assessment and end of treatment in pediatric Hodgkin lymphoma (HL) are limited. Methods: Patients (≤18 y) with HL were prospectively evaluated with contrast-enhanced CT (CECT) and PET combined with low-dose CT (PET/CT) at baseline, after 2 cycles of chemotherapy, and after completion of treatment. Revised International Working Group (RIW) criteria and Deauville 5 point-scale for response assessment by PET/CT were used. All patients received doxorubicin (Adriamycin), bleomycin, vinblastine, dacarbazine chemotherapy along with involved-field radiotherapy (25 Gy) for early stage (IA, IB, and IIA) and advanced stage (IIB-IV) with bulky disease. Results: Of the 57 enrolled patients, median follow-up was 81.6 mo (range, 11-97.5 mo). Treatment decisions were based on CECT. At baseline, PET/CT versus CECT identified 67 more disease sites; 23 patients (40.3%) were upstaged and of them in 9 patients (39%) upstaging would have affected treatment decision; notably none of these patients relapsed. The specificity of interim PET/CT based on RIW criteria (61.5%) and Deauville criteria (91.4%) for predicting relapse was higher than CECT (40.3%) (P = 0.03 and P < 0.0001, respectively). Event-free survival based on interim PET/CT (RIW) response was 93.3 ± 4.1 versus 89.6 ± 3.8 (positive vs. negative scan, respectively; P = 0.44). The specificity of posttreatment PET/CT (Deauville) was 95.7% versus 76.4% by CECT (P = 0.006). Posttreatment PET/CT (Deauville) showed significantly inferior overall survival in patients with positive scan versus negative scan results (66.4 ± 22.5 vs. 94.5 ± 2.0, P = 0.029). Conclusion: Interim PET/CT has better specificity, and use of Deauville criteria further improves it. Escalation of therapy based on interim PET in pediatric HL needs further conclusive evidence to justify its use. Posttreatment PET/CT (Deauville) predicts overall survival and has better specificity in comparison to

  13. Askin tumor: CT and FDG-PET/CT imaging findings and follow-up.

    PubMed

    Xia, Tingting; Guan, Yubao; Chen, Yongxin; Li, Jingxu

    2014-07-01

    The aim of the study was to describe the imaging findings of Askin tumors on computed tomography (CT) and fluorine 18 fluorodeoxyglucose-positron emission tomography (FDG-PET/CT).Seventeen cases of Askin tumors confirmed by histopathology were retrospectively analyzed in terms of CT (17 cases) and FDG-PET/CT data (6 cases).Fifteen of the tumors were located in the chest wall and the other 2 were in the anterior middle mediastinum. Of the 15 chest wall cases, 13 demonstrated irregular, heterogeneous soft tissue masses with cystic degeneration and necrosis, and 2 demonstrated homogeneous soft tissue masses on unenhanced CT scans. Two mediastinal tumors demonstrated the irregular, heterogeneous soft tissue masses. Calcifications were found in 2 tumors. The tumors demonstrated heterogeneously enhancement in 16 cases and homogeneous enhancement in 1 case on contrast-enhanced scans. FDG-PET/CT images revealed increased metabolic activity in all 6 cases undergone FDG-PET/CT scan, and the lesion SUVmax ranged from 4.0 to 18.6. At initial diagnosis, CT and FDG-PET/CT scans revealed rib destruction in 9 cases, pleural effusion in 9 cases, and lung metastasis in 1 case. At follow-up, 12 cases showed recurrence and/or metastases, 4 cases showed improvement or remained stable, and 1 was lost to follow-up.In summary, CT and FDG-PET/CT images of Askin tumors showed heterogeneous soft tissue masses in the chest wall and the mediastinum, accompanied by rib destruction, pleural effusion, and increased FDG uptake. CT and FDG-PET/CT imaging play important roles in the diagnosis and follow-up of patients with Askin tumors.

  14. Combined SPECT/CT and PET/CT for breast imaging

    NASA Astrophysics Data System (ADS)

    Russo, Paolo; Larobina, Michele; Di Lillo, Francesca; Del Vecchio, Silvana; Mettivier, Giovanni

    2016-02-01

    In the field of nuclear medicine imaging, breast imaging for cancer diagnosis is still mainly based on 2D imaging techniques. Three-dimensional tomographic imaging with whole-body PET or SPECT scanners, when used for imaging the breast, has performance limits in terms of spatial resolution and sensitivity, which can be overcome only with a dedicated instrumentation. However, only few hybrid imaging systems for PET/CT or SPECT/CT dedicated to the breast have been developed in the last decade, providing complementary functional and anatomical information on normal breast tissue and lesions. These systems are still under development and clinical trials on just few patients have been reported; no commercial dedicated breast PET/CT or SPECT/CT is available. This paper reviews combined dedicated breast PET/CT and SPECT/CT scanners described in the recent literature, with focus on their technological aspects.

  15. Feasibility study of small animal imaging using clinical PET/CT scanner

    NASA Astrophysics Data System (ADS)

    Hsu, Wen-Lin; Chen, Chia-Lin; Wang, Ze-Jing; Wu, Tung-Hsin; Liu, Dai-Wei; Lee, Jason J. S.

    2007-02-01

    The feasibility of small animal imaging using a clinical positron emission tomography/computed tomography (PET/CT) scanner with [F-18]-fluoro-2-deoxy- D-glucose (FDG) was evaluated. Two protocols in PET/CT system, single-mouse high-resolution mode (SHR) and multi-mouse high throughput mode (MHT) protocol were employed to investigate the ability of the scanner and also explored the performance differences between microPET and clinical PET/CT. In this study, we have found that even the clinical PET/CT scanner could not compete with the microPET scanner, especially in spatial resolution; the high-resolution CT image could advance the anatomical information to sub-millimeter level. Besides, CT-based attenuation correction can improve the image uniformity characteristics and quantification accuracy, and the large bore of a human whole-body scanner broadens the possibility of high throughput studies. Considering all the benefits, clinical PET/CT imaging might be a potential alternative for small animal study.

  16. Brain tissue segmentation in PET-CT images using probabilistic atlas and variational Bayes inference.

    PubMed

    Xia, Yong; Wang, Jiabin; Eberl, Stefan; Fulham, Michael; Feng, David Dagan

    2011-01-01

    PET-CT provides aligned anatomical (CT) and functional (PET) images in a single scan, and has the potential to improve brain PET image segmentation, which can in turn improve quantitative clinical analyses. We propose a statistical segmentation algorithm that incorporates the prior anatomical knowledge represented by probabilistic brain atlas into the variational Bayes inference to delineate gray matter (GM), white matter (WM) and cerebrospinal fluid (CSF) in brain PET-CT images. Our approach adds an additional novel aspect by allowing voxels to have variable and adaptive prior probabilities of belonging to each class. We compared our algorithm to the segmentation approaches implemented in the expectation maximization segmentation (EMS) and statistical parametric mapping (SPM8) packages in 26 clinical cases. The results show that our algorithm improves the accuracy of brain PET-CT image segmentation.

  17. Adrenal masses of varied etiology: anatomical and molecular imaging features on PET-CT.

    PubMed

    Sharma, Punit; Singh, Harmandeep; Dhull, Varun Singh; Suman KC, Sudhir; Kumar, Abhishek; Bal, Chandrasekhar; Kumar, Rakesh

    2014-03-01

    A wide spectrum of benign and malignant diseases can present as an adrenal mass. Combined PET-CT is useful for evaluation of adrenocortical and adrenomedullary masses. F-FDG has been extensively used as PET radiotracer for this purpose. F-FDOPA PET, Ga-DOTA peptide (Ga-DOTANOC/TATE) PET, and C-HED PET have also been used for imaging of adrenal medullary lesions, whereas C-MTO PET has been used for adrenocortical imaging. We provide a review of imaging characteristics of adrenal gland pathologies on PET-CT using different tracers.

  18. Joint Segmentation of Anatomical and Functional Images: Applications in Quantification of Lesions from PET, PET-CT, MRI-PET, and MRI-PET-CT Images

    PubMed Central

    Bagci, Ulas; Udupa, Jayaram K.; Mendhiratta, Neil; Foster, Brent; Xu, Ziyue; Yao, Jianhua; Chen, Xinjian; Mollura, Daniel J.

    2013-01-01

    We present a novel method for the joint segmentation of anatomical and functional images. Our proposed methodology unifies the domains of anatomical and functional images, represents them in a product lattice, and performs simultaneous delineation of regions based on random walk image segmentation. Furthermore, we also propose a simple yet effective object/background seed localization method to make the proposed segmentation process fully automatic. Our study uses PET, PET-CT, MRI-PET, and fused MRI-PET-CT scans (77 studies in all) from 56 patients who had various lesions in different body regions. We validated the effectiveness of the proposed method on different PET phantoms as well as on clinical images with respect to the ground truth segmentation provided by clinicians. Experimental results indicate that the presented method is superior to threshold and Bayesian methods commonly used in PET image segmentation, is more accurate and robust compared to the other PET-CT segmentation methods recently published in the literature, and also it is general in the sense of simultaneously segmenting multiple scans in real-time with high accuracy needed in routine clinical use. PMID:23837967

  19. Automated Movement Correction for Dynamic PET/CT Images: Evaluation with Phantom and Patient Data

    PubMed Central

    Ye, Hu; Wong, Koon-Pong; Wardak, Mirwais; Dahlbom, Magnus; Kepe, Vladimir; Barrio, Jorge R.; Nelson, Linda D.; Small, Gary W.; Huang, Sung-Cheng

    2014-01-01

    Head movement during a dynamic brain PET/CT imaging results in mismatch between CT and dynamic PET images. It can cause artifacts in CT-based attenuation corrected PET images, thus affecting both the qualitative and quantitative aspects of the dynamic PET images and the derived parametric images. In this study, we developed an automated retrospective image-based movement correction (MC) procedure. The MC method first registered the CT image to each dynamic PET frames, then re-reconstructed the PET frames with CT-based attenuation correction, and finally re-aligned all the PET frames to the same position. We evaluated the MC method's performance on the Hoffman phantom and dynamic FDDNP and FDG PET/CT images of patients with neurodegenerative disease or with poor compliance. Dynamic FDDNP PET/CT images (65 min) were obtained from 12 patients and dynamic FDG PET/CT images (60 min) were obtained from 6 patients. Logan analysis with cerebellum as the reference region was used to generate regional distribution volume ratio (DVR) for FDDNP scan before and after MC. For FDG studies, the image derived input function was used to generate parametric image of FDG uptake constant (Ki) before and after MC. Phantom study showed high accuracy of registration between PET and CT and improved PET images after MC. In patient study, head movement was observed in all subjects, especially in late PET frames with an average displacement of 6.92 mm. The z-direction translation (average maximum = 5.32 mm) and x-axis rotation (average maximum = 5.19 degrees) occurred most frequently. Image artifacts were significantly diminished after MC. There were significant differences (P<0.05) in the FDDNP DVR and FDG Ki values in the parietal and temporal regions after MC. In conclusion, MC applied to dynamic brain FDDNP and FDG PET/CT scans could improve the qualitative and quantitative aspects of images of both tracers. PMID:25111700

  20. Automated movement correction for dynamic PET/CT images: evaluation with phantom and patient data.

    PubMed

    Ye, Hu; Wong, Koon-Pong; Wardak, Mirwais; Dahlbom, Magnus; Kepe, Vladimir; Barrio, Jorge R; Nelson, Linda D; Small, Gary W; Huang, Sung-Cheng

    2014-01-01

    Head movement during a dynamic brain PET/CT imaging results in mismatch between CT and dynamic PET images. It can cause artifacts in CT-based attenuation corrected PET images, thus affecting both the qualitative and quantitative aspects of the dynamic PET images and the derived parametric images. In this study, we developed an automated retrospective image-based movement correction (MC) procedure. The MC method first registered the CT image to each dynamic PET frames, then re-reconstructed the PET frames with CT-based attenuation correction, and finally re-aligned all the PET frames to the same position. We evaluated the MC method's performance on the Hoffman phantom and dynamic FDDNP and FDG PET/CT images of patients with neurodegenerative disease or with poor compliance. Dynamic FDDNP PET/CT images (65 min) were obtained from 12 patients and dynamic FDG PET/CT images (60 min) were obtained from 6 patients. Logan analysis with cerebellum as the reference region was used to generate regional distribution volume ratio (DVR) for FDDNP scan before and after MC. For FDG studies, the image derived input function was used to generate parametric image of FDG uptake constant (Ki) before and after MC. Phantom study showed high accuracy of registration between PET and CT and improved PET images after MC. In patient study, head movement was observed in all subjects, especially in late PET frames with an average displacement of 6.92 mm. The z-direction translation (average maximum = 5.32 mm) and x-axis rotation (average maximum = 5.19 degrees) occurred most frequently. Image artifacts were significantly diminished after MC. There were significant differences (P<0.05) in the FDDNP DVR and FDG Ki values in the parietal and temporal regions after MC. In conclusion, MC applied to dynamic brain FDDNP and FDG PET/CT scans could improve the qualitative and quantitative aspects of images of both tracers.

  1. (18)F-NaF PET/CT: EANM procedure guidelines for bone imaging.

    PubMed

    Beheshti, M; Mottaghy, F M; Payche, F; Behrendt, F F F; Van den Wyngaert, T; Fogelman, I; Strobel, K; Celli, M; Fanti, S; Giammarile, F; Krause, B; Langsteger, W

    2015-10-01

    The aim of this guideline is to provide minimum standards for the performance and interpretation of (18)F-NaF PET/CT scans. Standard acquisition and interpretation of nuclear imaging modalities will help to provide consistent data acquisition and numeric values between different platforms and institutes and to promote the use of PET/CT modality as an established diagnostic modality in routine clinical practice. This will also improve the value of scientific work and its contribution to evidence-based medicine.

  2. Algorithm for lung cancer detection based on PET/CT images

    NASA Astrophysics Data System (ADS)

    Saita, Shinsuke; Ishimatsu, Keita; Kubo, Mitsuru; Kawata, Yoshiki; Niki, Noboru; Ohtsuka, Hideki; Nishitani, Hiromu; Ohmatsu, Hironobu; Eguchi, Kenji; Kaneko, Masahiro; Moriyama, Noriyuki

    2009-02-01

    The five year survival rate of the lung cancer is low with about twenty-five percent. In addition it is an obstinate lung cancer wherein three out of four people die within five years. Then, the early stage detection and treatment of the lung cancer are important. Recently, we can obtain CT and PET image at the same time because PET/CT device has been developed. PET/CT is possible for a highly accurate cancer diagnosis because it analyzes quantitative shape information from CT image and FDG distribution from PET image. However, neither benign-malignant classification nor staging intended for lung cancer have been established still enough by using PET/CT images. In this study, we detect lung nodules based on internal organs extracted from CT image, and we also develop algorithm which classifies benignmalignant and metastatic or non metastatic lung cancer using lung structure and FDG distribution(one and two hour after administering FDG). We apply the algorithm to 59 PET/CT images (malignant 43 cases [Ad:31, Sq:9, sm:3], benign 16 cases) and show the effectiveness of this algorithm.

  3. Moving Beyond "Lumpology": PET/CT Imaging of Pheochromocytoma and Paraganglioma.

    PubMed

    Hofman, Michael S; Hicks, Rodney J

    2015-09-01

    High somatostatin receptor expression on the cell membrane of succinate dehydrogenase mutation-related pheochromocytoma and paraganglioma provides a potential target for imaging and therapy. (68)Ga-DOTATATE positron emission PET/CT may represent a new gold standard for staging pheochromocytoma/paraganglioma and have future therapeutic implications.

  4. Segmentation of brain PET-CT images based on adaptive use of complementary information

    NASA Astrophysics Data System (ADS)

    Xia, Yong; Wen, Lingfeng; Eberl, Stefan; Fulham, Michael; Feng, Dagan

    2009-02-01

    Dual modality PET-CT imaging provides aligned anatomical (CT) and functional (PET) images in a single scanning session, which can potentially be used to improve image segmentation of PET-CT data. The ability to distinguish structures for segmentation is a function of structure and modality and varies across voxels. Thus optimal contribution of a particular modality to segmentation is spatially variant. Existing segmentation algorithms, however, seldom account for this characteristic of PET-CT data and the results using these algorithms are not optimal. In this study, we propose a relative discrimination index (RDI) to characterize the relative abilities of PET and CT to correctly classify each voxel into the correct structure for segmentation. The definition of RDI is based on the information entropy of the probability distribution of the voxel's class label. If the class label derived from CT data for a particular voxel has more certainty than that derived from PET data, the corresponding RDI will have a higher value. We applied the RDI matrix to balance adaptively the contributions of PET and CT data to segmentation of brain PET-CT images on a voxel-by-voxel basis, with the aim to give the modality with higher discriminatory power a larger weight. The resultant segmentation approach is distinguished from traditional approaches by its innovative and adaptive use of the dual-modality information. We compared our approach to the non-RDI version and two commonly used PET-only based segmentation algorithms for simulation and clinical data. Our results show that the RDI matrix markedly improved PET-CT image segmentation.

  5. 64CuCl2 PET/CT imaging of mouse muscular injury induced by electroporation

    PubMed Central

    Xie, Fang; Cai, Huawei; Peng, Fangyu

    2017-01-01

    Skeletal muscle injury is common in body injuries suffered in sports and car accidents. Development of new tracers is significant for assessing muscular injury with positron emission tomography/computed tomography (PET/CT) and monitoring repair of muscle injury in response to treatment. Copper is required for wound healing and increased copper ions were detected in the soft tissue of wound in rodents and human. Based on the recent finding of increased 64Cu uptake in the traumatic brain injury, this study aimed to explore use of 64CuCl2 as a radiotracer for molecular imaging of muscular injury using PET/CT. Focally increased 64Cu uptake by the injured muscular tissue (5.4 ± 1.2% ID/g) was detected in the C57BL/6 mice with electroporation-induced skeletal muscle injury by PET/CT after intravenous injection of 64CuCl2 as a tracer, compared to low 64Cu uptake associated with muscular inflammation induced by intramuscular injection of lipopolysaccharides (0.82 ± 0.26% ID/g, P < 0.01) or physiological 64Cu uptake of the non-injured muscular tissues (0.78 ± 0.20% ID/g, P < 0.01). The findings support further investigation of 64CuCl2 as a new radiotracer for molecular imaging of skeletal muscle injury using PET/CT. PMID:28123866

  6. State of the art imaging of multiple myeloma: comparative review of FDG PET/CT imaging in various clinical settings.

    PubMed

    Mesguich, Charles; Fardanesh, Reza; Tanenbaum, Lawrence; Chari, Ajai; Jagannath, Sundar; Kostakoglu, Lale

    2014-12-01

    18-Flurodeoxyglucose Positron Emission Tomography with computed tomography (FDG PET/CT) and Magnetic Resonance Imaging (MRI) have higher sensitivity and specificity than whole-body X-ray (WBXR) survey in evaluating disease extent in patients with multiple myeloma (MM). Both modalities are now recommended by the Durie-Salmon Plus classification although the emphasis is more on MRI than PET/CT. The presence of extra-medullary disease (EMD) as evaluated by PET/CT imaging, initial SUVmax and number of focal lesions (FL) are deemed to be strong prognostic parameters at staging. MRI remains the most sensitive technique for the detection of diffuse bone marrow involvement in both the pre and post-therapy setting. Compression fractures are best characterized with MRI signal changes, for determining vertebroplasty candidates. While PET/CT allows for earlier and more specific evaluation of therapeutic efficacy compared to MRI, when signal abnormalities persist years after treatment. PET/CT interpretation, however, can be challenging in the vertebral column and pelvis as well as in cases with post-therapy changes. Hence, a reading approach combining the high sensitivity of MRI and superior specificity of FDG PET/CT would be preferred to increase the diagnostic accuracy. In summary, the established management methods in MM, mainly relying on biological tumor parameters should be complemented with functional imaging data, both at staging and restaging for optimal management of MM.

  7. Automatic anatomy recognition in whole-body PET/CT images

    SciTech Connect

    Wang, Huiqian; Udupa, Jayaram K. Odhner, Dewey; Tong, Yubing; Torigian, Drew A.; Zhao, Liming

    2016-01-15

    Purpose: Whole-body positron emission tomography/computed tomography (PET/CT) has become a standard method of imaging patients with various disease conditions, especially cancer. Body-wide accurate quantification of disease burden in PET/CT images is important for characterizing lesions, staging disease, prognosticating patient outcome, planning treatment, and evaluating disease response to therapeutic interventions. However, body-wide anatomy recognition in PET/CT is a critical first step for accurately and automatically quantifying disease body-wide, body-region-wise, and organwise. This latter process, however, has remained a challenge due to the lower quality of the anatomic information portrayed in the CT component of this imaging modality and the paucity of anatomic details in the PET component. In this paper, the authors demonstrate the adaptation of a recently developed automatic anatomy recognition (AAR) methodology [Udupa et al., “Body-wide hierarchical fuzzy modeling, recognition, and delineation of anatomy in medical images,” Med. Image Anal. 18, 752–771 (2014)] to PET/CT images. Their goal was to test what level of object localization accuracy can be achieved on PET/CT compared to that achieved on diagnostic CT images. Methods: The authors advance the AAR approach in this work in three fronts: (i) from body-region-wise treatment in the work of Udupa et al. to whole body; (ii) from the use of image intensity in optimal object recognition in the work of Udupa et al. to intensity plus object-specific texture properties, and (iii) from the intramodality model-building-recognition strategy to the intermodality approach. The whole-body approach allows consideration of relationships among objects in different body regions, which was previously not possible. Consideration of object texture allows generalizing the previous optimal threshold-based fuzzy model recognition method from intensity images to any derived fuzzy membership image, and in the process

  8. Metal artifact reduction strategies for improved attenuation correction in hybrid PET/CT imaging

    SciTech Connect

    Abdoli, Mehrsima; Dierckx, Rudi A. J. O.; Zaidi, Habib

    2012-06-15

    Metallic implants are known to generate bright and dark streaking artifacts in x-ray computed tomography (CT) images, which in turn propagate to corresponding functional positron emission tomography (PET) images during the CT-based attenuation correction procedure commonly used on hybrid clinical PET/CT scanners. Therefore, visual artifacts and overestimation and/or underestimation of the tracer uptake in regions adjacent to metallic implants are likely to occur and as such, inaccurate quantification of the tracer uptake and potential erroneous clinical interpretation of PET images is expected. Accurate quantification of PET data requires metal artifact reduction (MAR) of the CT images prior to the application of the CT-based attenuation correction procedure. In this review, the origins of metallic artifacts and their impact on clinical PET/CT imaging are discussed. Moreover, a brief overview of proposed MAR methods and their advantages and drawbacks is presented. Although most of the presented MAR methods are mainly developed for diagnostic CT imaging, their potential application in PET/CT imaging is highlighted. The challenges associated with comparative evaluation of these methods in a clinical environment in the absence of a gold standard are also discussed.

  9. A Rare Case of Omentum Invasive Prostate Cancer: Staging With PSMA PET/CT Imaging and Response to Systemic Therapy.

    PubMed

    Ladwa, Rahul; Gustafson, Sonja; McCaffrey, Elizabeth; Miles, Kenneth; O'Byrne, Kenneth

    2017-02-24

    The omentum is a rare metastatic site for prostatic adenocarcinoma. We present a case of metastatic castrate-resistant prostate cancer, with progressive omentum invasive prostate cancer identified on prostate-specific membrane antigen (PSMA) PET/CT scan. Omental biopsy revealed metastatic prostate adenocarcinoma, and cabazitaxel chemotherapy was instituted with a prostate-specific antigen biochemical response. Repeat PSMA PET/CT imaging revealed increased avidity in omental metastasis. Despite prostate-specific antigen response, PSMA PET/CT did not correlate with a therapeutic response.

  10. (68)Ga-Pentixafor-PET/CT for Imaging of Chemokine Receptor 4 Expression in Glioblastoma.

    PubMed

    Lapa, Constantin; Lückerath, Katharina; Kleinlein, Irene; Monoranu, Camelia Maria; Linsenmann, Thomas; Kessler, Almuth F; Rudelius, Martina; Kropf, Saskia; Buck, Andreas K; Ernestus, Ralf-Ingo; Wester, Hans-Jürgen; Löhr, Mario; Herrmann, Ken

    2016-01-01

    Chemokine receptor-4 (CXCR4) has been reported to be overexpressed in glioblastoma (GBM) and to be associated with poor survival. This study investigated the feasibility of non-invasive CXCR4-directed imaging with positron emission tomography/computed tomography (PET/CT) using the radiolabelled chemokine receptor ligand (68)Ga-Pentixafor. 15 patients with clinical suspicion on primary or recurrent glioblastoma (13 primary, 2 recurrent tumors) underwent (68)Ga-Pentixafor-PET/CT for assessment of CXCR4 expression prior to surgery. O-(2-(18)F-fluoroethyl)-L-tyrosine ((18)F-FET) PET/CT images were available in 11/15 cases and were compared visually and semi-quantitatively (SUVmax, SUVmean). Tumor-to-background ratios (TBR) were calculated for both PET probes. (68)Ga-Pentixafor-PET/CT results were also compared to histological CXCR4 expression on neuronavigated surgical samples. (68)Ga-Pentixafor-PET/CT was visually positive in 13/15 cases with SUVmean and SUVmax of 3.0±1.5 and 3.9±2.0 respectively. Respective values for (18)F-FET were 4.4±2.0 (SUVmean) and 5.3±2.3 (SUVmax). TBR for SUVmean and SUVmax were higher for (68)Ga-Pentixafor than for (18)F-FET (SUVmean 154.0±90.7 vs. 4.1±1.3; SUVmax 70.3±44.0 and 3.8±1.2, p<0.01), respectively. Histological analysis confirmed CXCR4 expression in tumor areas with high (68)Ga-Pentixafor uptake; regions of the same tumor without apparent (68)Ga-Pentixafor uptake showed no or low receptor expression. In this pilot study, (68)Ga-Pentixafor retention has been observed in the vast majority of glioblastoma lesions and served as readout for non-invasive determination of CXCR4 expression. Given the paramount importance of the CXCR4/SDF-1 axis in tumor biology, (68)Ga-Pentixafor-PET/CT might prove a useful tool for sensitive, non-invasive in-vivo quantification of CXCR4 as well as selection of patients who might benefit from CXCR4-directed therapy.

  11. Adrenal tuberculosis masquerading as disseminated malignancy: A pitfall of (18)F-FDG PET/CT Imaging.

    PubMed

    Gorla, A K R; Gupta, K; Sood, A; Biswal, C K; Bhansali, A; Mittal, B R

    2016-01-01

    Non-invasive characterization of adrenal lesions is a commonly encountered diagnostic challenge. Characteristic clinical and correlative imaging findings may assist in only arriving at a probable diagnosis. Currently, (18)F-FDG PET/CT is considered to provide the most comprehensive imaging information. We here present a case of bilateral adrenal tuberculosis that highlights the need for caution during the interpretation of (18)F-FDG PET/CT and also the need to suggest histopathological correlation.

  12. F18 EF5 PET/CT Imaging in Patients with Brain Metastases from Breast Cancer

    DTIC Science & Technology

    2013-07-01

    with Brain Metastases from Breast Cancer PRINCIPAL INVESTIGATOR: Lilie Lin, MD CONTRACTING ORGANIZATION: University of Pennsylvania...Annual 3. DATES COVERED 01 July 2012 to 30 June 2013 4. TITLE AND SUBTITLE F18 EF5 PET/CT Imaging in Patients with Brain Metastases from Breast 5a...SUPPLEMENTARY NOTES 14. ABSTRACT The aim of this study is to estimate the degree of residual hypoxia after whole brain radiation therapy in patients

  13. Particle Disease on Fluoride-18 (NaF) PET/CT imaging

    PubMed Central

    Kuo, Jonathan; Foster, Cameron; Shelton, David

    2011-01-01

    Particle disease is a loss of bone that commonly occurs about five years after arthroplasty. The cause is secondary to microabrasive wear and shedding of any portion of the prosthesis, and the microscopic foreign bodies activate inflammation which can lead to pain. This report describes the imaging findings of an 80-year-old female with particle disease detected with 18F-fluoride PET/CT. PMID:22470793

  14. TH-E-202-01: Pitfalls and Remedies in PET/CT Imaging for RT Planning.

    PubMed

    Pan, T

    2016-06-01

    PET/CT is a very important imaging tool in the management of oncology patients. PET/CT has been applied for treatment planning and response evaluation in radiation therapy. This educational session will discuss: 1. Pitfalls and remedies in PET/CT imaging for RT planning 2. The use of hypoxia PET imaging for radiotherapy 3. PET for tumor response evaluation The first presentation will address the issue of mis-registration between the CT and PET images in the thorax and the abdomen. We will discuss the challenges of respiratory gating and introduce an average CT technique to improve the registration for dose calculation and image-guidance in radiation therapy. The second presentation will discuss the use of hypoxia PET Imaging for radiation therapy. We will discuss various hypoxia radiotracers, the choice of clinical acquisition protocol (in particular a single late static acquisition versus a dynamic acquisition), and the compartmental modeling with different transfer rate constants explained. We will demonstrate applications of hypoxia imaging for dose escalation/de-escalation in clinical trials. The last presentation will discuss the use of PET/CT for tumor response evaluation. We will discuss anatomic response assessment vs. metabolic response assessment, visual evaluation and semi-quantitative evaluation, and limitations of current PET/CT assessment. We will summarize clinical trials using PET response in guiding adaptive radiotherapy. Finally, we will summarize recent advancements in PET/CT radiomics and non-FDG PET tracers for response assessment.

  15. Automated cardiac motion compensation in PET/CT for accurate reconstruction of PET myocardial perfusion images

    NASA Astrophysics Data System (ADS)

    Khurshid, Khawar; McGough, Robert J.; Berger, Kevin

    2008-10-01

    Error-free reconstruction of PET data with a registered CT attenuation map is essential for accurate quantification and interpretation of cardiac perfusion. Misalignment of the CT and PET data can produce an erroneous attenuation map that projects lung attenuation parameters onto the heart wall, thereby underestimating the attenuation and creating artifactual areas of hypoperfusion that can be misinterpreted as myocardial ischemia or infarction. The major causes of misregistration between CT and PET images are the respiratory motion, cardiac motion and gross physical motion of the patient. The misalignment artifact problem is overcome with automated cardiac registration software that minimizes the alignment error between the two modalities. Results show that the automated registration process works equally well for any respiratory phase in which the CT scan is acquired. Further evaluation of this procedure on 50 patients demonstrates that the automated registration software consistently aligns the two modalities, eliminating artifactual hypoperfusion in reconstructed PET images due to PET/CT misregistration. With this registration software, only one CT scan is required for PET/CT imaging, which reduces the radiation dose required for CT-based attenuation correction and improves the clinical workflow for PET/CT.

  16. SU-E-J-222: Evaluation of Deformable Registration of PET/CT Images for Cervical Cancer Brachytherapy

    SciTech Connect

    Liao, Y; Turian, J; Templeton, A; Kiel, K; Chu, J; Kadir, T

    2014-06-01

    Purpose: PET/CT provides important functional information for radiotherapy targeting of cervical cancer. However, repeated PET/CT procedures for external beam and subsequent brachytherapy expose patients to additional radiation and are not cost effective. Our goal is to investigate the possibility of propagating PET-active volumes for brachytherapy procedures through deformable image registration (DIR) of earlier PET/CT and ultimately to minimize the number of PET/CT image sessions required. Methods: Nine cervical cancer patients each received their brachytherapy preplanning PET/CT at the end of EBRT with a Syed template in place. The planning PET/CT was acquired on the day of brachytherapy treatment with the actual applicator (Syed or Tandem and Ring) and rigidly registered. The PET/CT images were then deformably registered creating a third (deformed) image set for target prediction. Regions of interest with standardized uptake values (SUV) greater than 65% of maximum SUV were contoured as target volumes in all three sets of PET images. The predictive value of the registered images was evaluated by comparing the preplanning and deformed PET volumes with the planning PET volume using Dice's coefficient (DC) and center-of-mass (COM) displacement. Results: The average DCs were 0.12±0.14 and 0.19±0.16 for rigid and deformable predicted target volumes, respectively. The average COM displacements were 1.9±0.9 cm and 1.7±0.7 cm for rigid and deformable registration, respectively. The DCs were improved by deformable registration, however, both were lower than published data for DIR in other modalities and clinical sites. Anatomical changes caused by different brachytherapy applicators could have posed a challenge to the DIR algorithm. The physiological change from interstitial needle placement may also contribute to lower DC. Conclusion: The clinical use of DIR in PET/CT for cervical cancer brachytherapy appears to be limited by applicator choice and requires further

  17. Diagnostic imaging in dermatology: utility of PET-CT in cutaneous melanoma.

    PubMed

    Sánchez-Sánchez, R; Serrano-Falcón, C; Rebollo Aguirre, A C

    2015-01-01

    Malignant melanoma accounts for 5% of all malignant skin tumors and its incidence is increasing. In the natural course of melanoma, tumors grow locally and can spread via the lymph system or the blood. Because survival is directly related to the stage of the disease at diagnosis, early detection (secondary prevention) has an impact on prognosis. Positron emission tomography (PET) is a nuclear medicine technique that generates images using molecules labeled with positron-emitting isotopes. The most widely used molecule is fluorodeoxyglucose (FDG). Because of the elevated glycolytic rate in tumor cells, which results in increased FDG uptake, greater quantities of FDG become trapped in tumor cells, enabling external detection. Today, most PET scanners are multimodal PET-computed tomography (CT) scanners, which provide more detailed information by combining morphological information with functional PET findings. The possible utility of PET-CT in patients with malignant melanoma is a subject of debate. Various questions have been raised: when the scan should be performed, whether PET-CT has advantages over conventional diagnostic methods, and whether PET-CT provides a real benefit to patients. In this review of the literature, we will analyze each of these questions.

  18. 68Ga-DOTATATE PET/CT imaging of indeterminate pulmonary nodules and lung cancer

    PubMed Central

    Walker, Ronald; Deppen, Stephen; Smith, Gary; Shi, Chanjuan; Lehman, Jonathan; Clanton, Jeff; Moore, Brandon; Burns, Rena; Grogan, Eric L.; Massion, Pierre P.

    2017-01-01

    Purpose 18F-FDG PET/CT is widely used to evaluate indeterminate pulmonary nodules (IPNs). False positive results occur, especially from active granulomatous nodules. A PET-based imaging agent with superior specificity to 18F-FDG for IPNs, is badly needed, especially in areas of endemic granulomatous nodules. Somatostatin receptors (SSTR) are expressed in many malignant cells including small cell and non-small cell lung cancers (NSCLCs). 68Ga-DOTATATE, a positron emitter labeled somatostatin analog, combined with PET/CT imaging, may improve the diagnosis of IPNs over 18F-FDG by reducing false positives. Our study purpose was to test this hypothesis in our region with high endemic granulomatous IPNs. Methods We prospectively performed 68Ga-DOTATATE PET/CT and 18F-FDG PET/CT scans in the same 30 patients with newly diagnosed, treatment-naïve lung cancer (N = 14) or IPNs (N = 15) and one metastatic nodule. 68Ga-DOTATATE SUVmax levels at or above 1.5 were considered likely malignant. We analyzed the scan results, correlating with ultimate diagnosis via biopsy or 2-year chest CT follow-up. We also correlated 68Ga-DOTATATE uptake with immunohistochemical (IHC) staining for SSTR subtype 2A (SSTR2A) in pathological specimens. Results We analyzed 31 lesions in 30 individuals, with 14 (45%) being non-neuroendocrine lung cancers and 1 (3%) being metastatic disease. McNemar’s result comparing the two radiopharmaceuticals (p = 0.65) indicates that their accuracy of diagnosis in this indication are equivalent. 68Ga-DOTATATE was more specific (94% compared to 81%) and less sensitive 73% compared to 93%) than 18F-FDG. 68Ga-DOTATATE uptake correlated with SSTR2A expression in tumor stroma determined by immunohistochemical (IHC) staining in 5 of 9 (55%) NSCLCs. Conclusion 68Ga-DOTATATE and 18F-FDG PET/CT had equivalent accuracy in the diagnosis of non-neuroendocrine lung cancer and 68Ga-DOTATATE was more specific than 18F-FDG for the diagnosis of IPNs. IHC staining for SSTR2A

  19. PET/CT imaging of abdominal aorta with intramural hematomas, penetrating ulcer, and saccular pseudoaneurysm.

    PubMed

    Nguyen, Vien X; Nguyen, Ba D

    2014-05-01

    Acute aortic syndromes, encompassing intramural hematoma, penetrating ulcer, and pseudoaneurysm, are best demonstrated by angiographic CT and magnetic resonance imaging. These imaging modalities provide an accurate evaluation and allow timely therapies of these frequently symptomatic lesions, thus reducing their morbidity and mortality. The inflammatory pathogenesis of these acute aortic syndromes may exhibit positive PET findings predictive of prognosis and outcomes of these vascular events. The authors present a case of PET/CT imaging showing asymptomatic intramural hematomas with penetrating ulcer and saccular pseudoaneurysm of the proximal abdominal aorta.

  20. 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

  1. Automatic co-segmentation of lung tumor based on random forest in PET-CT images

    NASA Astrophysics Data System (ADS)

    Jiang, Xueqing; Xiang, Dehui; Zhang, Bin; Zhu, Weifang; Shi, Fei; Chen, Xinjian

    2016-03-01

    In this paper, a fully automatic method is proposed to segment the lung tumor in clinical 3D PET-CT images. The proposed method effectively combines PET and CT information to make full use of the high contrast of PET images and superior spatial resolution of CT images. Our approach consists of three main parts: (1) initial segmentation, in which spines are removed in CT images and initial connected regions achieved by thresholding based segmentation in PET images; (2) coarse segmentation, in which monotonic downhill function is applied to rule out structures which have similar standardized uptake values (SUV) to the lung tumor but do not satisfy a monotonic property in PET images; (3) fine segmentation, random forests method is applied to accurately segment the lung tumor by extracting effective features from PET and CT images simultaneously. We validated our algorithm on a dataset which consists of 24 3D PET-CT images from different patients with non-small cell lung cancer (NSCLC). The average TPVF, FPVF and accuracy rate (ACC) were 83.65%, 0.05% and 99.93%, respectively. The correlation analysis shows our segmented lung tumor volumes has strong correlation ( average 0.985) with the ground truth 1 and ground truth 2 labeled by a clinical expert.

  2. Lymph node detection in IASLC-defined zones on PET/CT images

    NASA Astrophysics Data System (ADS)

    Song, Yihua; Udupa, Jayaram K.; Odhner, Dewey; Tong, Yubing; Torigian, Drew A.

    2016-03-01

    Lymph node detection is challenging due to the low contrast between lymph nodes as well as surrounding soft tissues and the variation in nodal size and shape. In this paper, we propose several novel ideas which are combined into a system to operate on positron emission tomography/ computed tomography (PET/CT) images to detect abnormal thoracic nodes. First, our previous Automatic Anatomy Recognition (AAR) approach is modified where lymph node zones predominantly following International Association for the Study of Lung Cancer (IASLC) specifications are modeled as objects arranged in a hierarchy along with key anatomic anchor objects. This fuzzy anatomy model built from diagnostic CT images is then deployed on PET/CT images for automatically recognizing the zones. A novel globular filter (g-filter) to detect blob-like objects over a specified range of sizes is designed to detect the most likely locations and sizes of diseased nodes. Abnormal nodes within each automatically localized zone are subsequently detected via combined use of different items of information at various scales: lymph node zone model poses found at recognition indicating the geographic layout at the global level of node clusters, g-filter response which hones in on and carefully selects node-like globular objects at the node level, and CT and PET gray value but within only the most plausible nodal regions for node presence at the voxel level. The models are built from 25 diagnostic CT scans and refined for an object hierarchy based on a separate set of 20 diagnostic CT scans. Node detection is tested on an additional set of 20 PET/CT scans. Our preliminary results indicate node detection sensitivity and specificity at around 90% and 85%, respectively.

  3. Pulmonary nodule detection in PET/CT images: improved approach using combined nodule detection and hybrid FP reduction

    NASA Astrophysics Data System (ADS)

    Teramoto, Atsushi; Fujita, Hiroshi; Tomita, Yoya; Takahashi, Katsuaki; Yamamuro, Osamu; Tamaki, Tsuneo

    2012-03-01

    In this study, an automated scheme for detecting pulmonary nodules in PET/CT images has been proposed using combined detection and hybrid false-positive (FP) reduction techniques. The initial nodule candidates were detected separately from CT and PET images. FPs were then eliminated in the initial candidates by using support vector machine with characteristic values obtained from CT and PET images. In the experiment, we evaluated proposed method using 105 cases of PET/CT images that were obtained in the cancer-screening program. We evaluated true positive fraction (TPF) and FP / case. As a result, TPFs of CT and PET detections were 0.76 and 0.44, respectively. However, by integrating the both results, TPF was reached to 0.82 with 5.14 FPs/case. These results indicate that our method may be of practical use for the detection of pulmonary nodules using PET/CT images.

  4. Primary Pulmonary Artery Sarcoma on Dual-Time Point FDG PET/CT Imaging.

    PubMed

    Li, Juan; Zhao, Qian; He, Lirong; Zhuang, Xiaoqing; Li, Fang

    2016-08-01

    A 59-year-old man presented cough, chest pain, and shortness of breath for 2 weeks and fever for 4 days. A contrast chest CT revealed a large right pulmonary artery filling defect, suggestive of pulmonary embolism that failed to respond to anticoagulation therapy. FDG PET/CT was performed to evaluate possible malignancy, which revealed intense activity in the right main pulmonary artery without any extrathoracic abnormality. The ratio of the SUVmax of this lesion to the liver was significantly increased in the delayed PET images. The pathological examination demonstrated primary pulmonary artery sarcoma.

  5. Fireworks-induced chest wall granulomatous disease: 18F-FDG PET/CT imaging.

    PubMed

    Le, Stephanie T; Nguyen, Ba Duong

    2014-04-01

    The authors present a case of 18F-FDG-avid granulomatous reaction induced by fireworks injury of the chest wall in a patient with esophageal adenocarcinoma. This hypermetabolic lesion, involving the right pectoralis muscles, appeared slightly more prominent on restaging PET/CT imaging following chemotherapy and radiation therapy. Excisional biopsy of the lesion established the diagnosis of foreign-body granulomatous-type inflammation with surrounding foci of non-polarizable black foreign material and ruled out malignancy. The patient recalled accidentally shooting himself in the chest with a Roman candle at the age of 3.

  6. 18F-FDG PET/CT Imaging of Gallbladder Adenocarcinoma - A Pictorial Review

    PubMed Central

    Awan, Omer; Khan, Salman A

    2015-01-01

    Gallbladder adenocarcinoma is an uncommon and serious disease. The primary disease grows rapidly with local invasion into the liver and with distant spread to lymph nodes. It is often detected late, due to which management can be challenging. Despite routine use of computed tomography (CT) and ultrasonography (US) for detection, magnetic resonance imaging (MRI) is often considered for a detailed assessment of the anatomic behavior of these tumors. We share three cases where 18-FDG PET/CT played a role in management thereof. PMID:26430572

  7. Optimal Co-segmentation of Tumor in PET-CT Images with Context Information

    PubMed Central

    Song, Qi; Bai, Junjie; Han, Dongfeng; Bhatia, Sudershan; Sun, Wenqing; Rockey, William; Bayouth, John E.; Buatti, John M.

    2014-01-01

    PET-CT images have been widely used in clinical practice for radiotherapy treatment planning of the radiotherapy. Many existing segmentation approaches only work for a single imaging modality, which suffer from the low spatial resolution in PET or low contrast in CT. In this work we propose a novel method for the co-segmentation of the tumor in both PET and CT images, which makes use of advantages from each modality: the functionality information from PET and the anatomical structure information from CT. The approach formulates the segmentation problem as a minimization problem of a Markov Random Field (MRF) model, which encodes the information from both modalities. The optimization is solved using a graph-cut based method. Two sub-graphs are constructed for the segmentation of the PET and the CT images, respectively. To achieve consistent results in two modalities, an adaptive context cost is enforced by adding context arcs between the two subgraphs. An optimal solution can be obtained by solving a single maximum flow problem, which leads to simultaneous segmentation of the tumor volumes in both modalities. The proposed algorithm was validated in robust delineation of lung tumors on 23 PET-CT datasets and two head-and-neck cancer subjects. Both qualitative and quantitative results show significant improvement compared to the graph cut methods solely using PET or CT. PMID:23693127

  8. Non-Target Activity Detection by Post-Radioembolization Yttrium-90 PET/CT: Image Assessment Technique and Case Examples

    PubMed Central

    Kao, Yung Hsiang; Tan, Andrew E. H.; Lo, Richard H. G.; Tay, Kiang Hiong; Tan, Bien Soo; Chow, Pierce K. H.; Ng, David C. E.; Goh, Anthony S. W.

    2013-01-01

    High resolution yttrium-90 (90Y) imaging of post-radioembolization microsphere biodistribution may be achieved by conventional positron emission tomography with integrated computed tomography (PET/CT) scanners that have time-of-flight capability. However, reconstructed 90Y PET/CT images have high background noise, making non-target activity detection technically challenging. This educational article describes our image assessment technique for non-target activity detection by 90Y PET/CT, which qualitatively overcomes the problem of background noise. We present selected case examples of non-target activity in untargeted liver, stomach, gallbladder, chest wall, and kidney, supported by angiography and 90Y bremsstrahlung single-photon emission computed tomography with integrated computed tomography (SPECT/CT) or technetium-99m macroaggregated albumin SPECT/CT. PMID:24551594

  9. 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.

  10. Characterization of PET/CT images using texture analysis: the past, the present… any future?

    PubMed Central

    Tixier, Florent; Pierce, Larry; Kinahan, Paul E.; Le Rest, Catherine Cheze; Visvikis, Dimitris

    2017-01-01

    After seminal papers over the period 2009 – 2011, the use of texture analysis of PET/CT images for quantification of intratumour uptake heterogeneity has received increasing attention in the last 4 years. Results are difficult to compare due to the heterogeneity of studies and lack of standardization. There are also numerous challenges to address. In this review we provide critical insights into the recent development of texture analysis for quantifying the heterogeneity in PET/CT images, identify issues and challenges, and offer recommendations for the use of texture analysis in clinical research. Numerous potentially confounding issues have been identified, related to the complex workflow for the calculation of textural features, and the dependency of features on various factors such as acquisition, image reconstruction, preprocessing, functional volume segmentation, and methods of establishing and quantifying correspondences with genomic and clinical metrics of interest. A lack of understanding of what the features may represent in terms of the underlying pathophysiological processes and the variability of technical implementation practices makes comparing results in the literature challenging, if not impossible. Since progress as a field requires pooling results, there is an urgent need for standardization and recommendations/guidelines to enable the field to move forward. We provide a list of correct formulae for usual features and recommendations regarding implementation. Studies on larger cohorts with robust statistical analysis and machine learning approaches are promising directions to evaluate the potential of this approach. PMID:27271051

  11. Image reconstruction for PET/CT scanners: past achievements and future challenges

    PubMed Central

    Tong, Shan; Alessio, Adam M; Kinahan, Paul E

    2011-01-01

    PET is a medical imaging modality with proven clinical value for disease diagnosis and treatment monitoring. The integration of PET and CT on modern scanners provides a synergy of the two imaging modalities. Through different mathematical algorithms, PET data can be reconstructed into the spatial distribution of the injected radiotracer. With dynamic imaging, kinetic parameters of specific biological processes can also be determined. Numerous efforts have been devoted to the development of PET image reconstruction methods over the last four decades, encompassing analytic and iterative reconstruction methods. This article provides an overview of the commonly used methods. Current challenges in PET image reconstruction include more accurate quantitation, TOF imaging, system modeling, motion correction and dynamic reconstruction. Advances in these aspects could enhance the use of PET/CT imaging in patient care and in clinical research studies of pathophysiology and therapeutic interventions. PMID:21339831

  12. Initial Characterization of a Dedicated Breast PET/CT Scanner During Human Imaging

    PubMed Central

    Bowen, Spencer L.; Wu, Yibao; Chaudhari, Abhijit J.; Fu, Lin; Packard, Nathan J.; Burkett, George W.; Yang, Kai; Lindfors, Karen K.; Shelton, David K.; Hagge, Rosalie; Borowsky, Alexander D.; Martinez, Steve R.; Qi, Jinyi; Boone, John M.; Cherry, Simon R.; Badawi, Ramsey D.

    2010-01-01

    We have constructed a dedicated breast PET/CT scanner capable of high-resolution functional and anatomic imaging. Here, we present an initial characterization of scanner performance during patient imaging. Methods The system consisted of a lutetium oxyorthosilicate–based dual–planar head PET camera (crystal size, 3 × 3 × 20 mm) and 768-slice cone-beam CT. The position of the PET heads (separation and height) could be adjusted for varying breast dimensions. For scanning, the patient lay prone on a specialized bed and inserted a single pendent breast through an aperture in the table top. Compression of the breast as used in mammography is not required. PET and CT systems rotate in the coronal plane underneath the patient sequentially to collect fully tomographic datasets. PET images were reconstructed with the fully 3-dimensional maximum a posteriori method, and CT images were reconstructed with the Feldkamp algorithm, then spatially registered and fused for display. Phantom scans were obtained to assess the registration accuracy between PET and CT images and the influence of PET electronics and activity on CT image quality. We imaged 4 women with mammographic findings highly suggestive of breast cancer (breast imaging reporting and data system, category 5) in an ongoing clinical trial. Patients were injected with 18F-FDG and imaged for 12.5 min per breast. From patient data, noise-equivalent counting rates and the singles-to-trues ratio (a surrogate for the randoms fraction) were calculated. Results The average registration error between PET and CT images was 0.18 mm. PET electronics and activity did not significantly affect CT image quality. For the patient trial, biopsy-confirmed cancers were visualized on dedicated breast PET/CT on all patient scans, including the detection of ductal carcinoma in situ in 1 case. The singles-to-trues ratio was found to be inversely correlated with breast volume in the field of view, suggesting that larger breasts trend

  13. Registration of parametric dynamic F-18-FDG PET/CT breast images with parametric dynamic Gd-DTPA breast images

    NASA Astrophysics Data System (ADS)

    Magri, Alphonso; Krol, Andrzej; Lipson, Edward; Mandel, James; McGraw, Wendy; Lee, Wei; Tillapaugh-Fay, Gwen; Feiglin, David

    2009-02-01

    This study was undertaken to register 3D parametric breast images derived from Gd-DTPA MR and F-18-FDG PET/CT dynamic image series. Nonlinear curve fitting (Levenburg-Marquardt algorithm) based on realistic two-compartment models was performed voxel-by-voxel separately for MR (Brix) and PET (Patlak). PET dynamic series consists of 50 frames of 1-minute duration. Each consecutive PET image was nonrigidly registered to the first frame using a finite element method and fiducial skin markers. The 12 post-contrast MR images were nonrigidly registered to the precontrast frame using a free-form deformation (FFD) method. Parametric MR images were registered to parametric PET images via CT using FFD because the first PET time frame was acquired immediately after the CT image on a PET/CT scanner and is considered registered to the CT image. We conclude that nonrigid registration of PET and MR parametric images using CT data acquired during PET/CT scan and the FFD method resulted in their improved spatial coregistration. The success of this procedure was limited due to relatively large target registration error, TRE = 15.1+/-7.7 mm, as compared to spatial resolution of PET (6-7 mm), and swirling image artifacts created in MR parametric images by the FFD. Further refinement of nonrigid registration of PET and MR parametric images is necessary to enhance visualization and integration of complex diagnostic information provided by both modalities that will lead to improved diagnostic performance.

  14. Dual-modality brain PET-CT image segmentation based on adaptive use of functional and anatomical information.

    PubMed

    Xia, Yong; Eberl, Stefan; Wen, Lingfeng; Fulham, Michael; Feng, David Dagan

    2012-01-01

    Dual medical imaging modalities, such as PET-CT, are now a routine component of clinical practice. Medical image segmentation methods, however, have generally only been applied to single modality images. In this paper, we propose the dual-modality image segmentation model to segment brain PET-CT images into gray matter, white matter and cerebrospinal fluid. This model converts PET-CT image segmentation into an optimization process controlled simultaneously by PET and CT voxel values and spatial constraints. It is innovative in the creation and application of the modality discriminatory power (MDP) coefficient as a weighting scheme to adaptively combine the functional (PET) and anatomical (CT) information on a voxel-by-voxel basis. Our approach relies upon allowing the modality with higher discriminatory power to play a more important role in the segmentation process. We compared the proposed approach to three other image segmentation strategies, including PET-only based segmentation, combination of the results of independent PET image segmentation and CT image segmentation, and simultaneous segmentation of joint PET and CT images without an adaptive weighting scheme. Our results in 21 clinical studies showed that our approach provides the most accurate and reliable segmentation for brain PET-CT images.

  15. A web-based image viewer for multiple PET-CT follow-up studies.

    PubMed

    Haraguchi, Daiki; Kim, Jinman; Kumar, Ashnil; Constantinescu, Liviu; Wen, Lingfeng; Feng, David Dagan

    2011-01-01

    There exist many viewers for single-modal medical images that are efficient and are equipped with powerful analysis tools. However, there is a distinct lack of efficient image viewers for multi-modality images, particularly for displaying multiple follow-up studies that depict a patient's response to treatment over time. Such viewers would be required to display large amounts of image data. In this study, we present the TAGIGEN viewer--a web-based image viewer designed specifically for the visualisation of multi-modality follow-up studies. We innovate by defining a series of dynamically generated image grid layouts that display sets of related images together in order to improve the ability to compare and assimilate the myriad images. We adopted a web-based client-server image streaming technology, thus enabling interactive navigation of the images in a computationally efficient manner. Furthermore, our web-based approach is interoperable and requires no software installation. We evaluated the ability of our viewer in displaying and understanding a patient's follow-up images in a case study with combined positron emission tomography and computed tomography (PET-CT) follow-up scans. We conducted a usability survey on 10 participants to measure the usefulness of our viewer, used as an outpatient viewer e.g. viewer designed for use by the patients, in tracking a patient's disease state across four PET-CT studies. Our initial results suggest that our viewer was able to efficiently visualise the patient data over time, and that the web-based implementation was fast (loading on average within 5.6 seconds with real-time navigation) and easy to use (overall survey score higher than 4 / 5).

  16. Impact of FDG-PET/CT Imaging on Nodal Staging for Head-And-Neck Squamous Cell Carcinoma

    SciTech Connect

    Murakami, Ryuji . E-mail: murakami@kaiju.medic.kumamoto-u.ac.jp; Uozumi, Hideaki; Hirai, Toshinori; Nishimura, Ryuichi; Shiraishi, Shinya; Ota, Kazutoshi D.D.S.; Murakami, Daizo; Tomiguchi, Seiji; Oya, Natsuo; Katsuragawa, Shigehiko; Yamashita, Yasuyuki

    2007-06-01

    Purpose: To evaluate the impact of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) imaging on nodal staging for head-and-neck squamous cell carcinoma (SCC). Methods and Materials: The study population consisted of 23 patients with head-and-neck SCC who were evaluated with FDG-PET/CT and went on to neck dissection. Two observers consensually determined the lesion size and maximum standardized uptake value (SUV{sub max}) and compared the results with pathologic findings on nodal-level involvement. Two different observers (A and B) independently performed three protocols for clinical nodal staging. Methods 1, 2, and 3 were based on conventional modalities, additional visual information from FDG-PET/CT images, and FDG-PET/CT imaging alone with SUV data, respectively. Results: All primary tumors were visualized with FDG-PET/CT. Pathologically, 19 positive and 93 negative nodal levels were identified. The SUV{sub max} overlapped in negative and positive nodes <15 mm in diameter. According to receiver operating characteristics analysis, the size-based SUV{sub max} cutoff values were 1.9, 2.5, and 3.0 for lymph nodes <10 mm, 10-15 mm, and >15 mm, respectively. These cutoff values yielded 79% sensitivity and 99% specificity for nodal-level staging. For Observer A, the sensitivity and specificity in Methods 1, 2, and 3 were 68% and 94%, 68% and 99%, and 84% and 99%, respectively, and Method 3 yielded significantly higher accuracy than Method 1 (p = 0.0269). For Observer B, Method 3 yielded the highest sensitivity (84%) and specificity (99%); however, the difference among the three protocols was not statistically significant. Conclusion: Imaging with FDG-PET/CT with size-based SUV{sub max} cutoff values is an important modality for radiation therapy planning.

  17. Qualification of NCI-Designated Cancer Centers for Quantitative PET/CT Imaging in Clinical Trials.

    PubMed

    Scheuermann, Joshua S; Reddin, Janet S; Opanowski, Adam; Kinahan, Paul E; Siegel, Barry A; Shankar, Lalitha K; Karp, Joel S

    2017-03-02

    The National Cancer Institute (NCI) developed the Centers for Quantitative Imaging Excellence (CQIE) initiative in 2010 to pre-qualify imaging facilities at all of the NCI-designated Comprehensive and Clinical Cancer Centers for oncology trials using advanced imaging techniques, including positron emission tomography (PET). This paper reviews the CQIE PET/CT (Computed Tomography) scanner qualification process and results in detail. Methods: Over a period of approximately 5 years, sites were requested to submit a variety of phantom, including uniform and ACR (American College of Radiology) phantoms, PET/CT images, as well as examples of clinical images. Submissions were divided into 3 distinct time points: initial submission (T0), followed by two requalification submissions (T1 and T2). Images were analyzed using standardized procedures and scanners received a pass or fail designation. Sites had the opportunity to submit new data for failed scanners. Quantitative results were compared: across scanners within a given time point and across time points for a given scanner. Results: 65 unique PET/CT scanners across 42 sites were submitted for CQIE T0 qualification, with 64 passing qualification. 44 (68%) of the scanners from T0 had data submitted for T2. From T0 to T2 the percentage of scanners passing the CQIE qualification on the first attempt rose from 38% in T1 to 67% in T2. The most common reasons for failure were: standardized uptake value (SUV) out of specifications, incomplete data submission and uniformity issues. Uniform phantom and ACR phantom results between scanner manufacturers are similar. Conclusion: The results of the CQIE process show that periodic requalification may decrease the frequency of deficient data submissions. The CQIE project also highlighted the concern within imaging facilities about the burden of maintaining different qualifications and accreditations. Finally, we note that for quantitative imaging-based trials the relationships between

  18. In vivo verification of proton beam path by using post-treatment PET/CT imaging

    SciTech Connect

    Hsi, Wen C.; Indelicato, Daniel J.; Vargas, Carlos; Duvvuri, Srividya; Li Zuofeng; Palta, Jatinder

    2009-09-15

    Purpose: The purpose of this study is to establish the in vivo verification of proton beam path by using proton-activated positron emission distributions. Methods: A total of 50 PET/CT imaging studies were performed on ten prostate cancer patients immediately after daily proton therapy treatment through a single lateral portal. The PET/CT and planning CT were registered by matching the pelvic bones, and the beam path of delivered protons was defined in vivo by the positron emission distribution seen only within the pelvic bones, referred to as the PET-defined beam path. Because of the patient position correction at each fraction, the marker-defined beam path, determined by the centroid of implanted markers seen in the post-treatment (post-Tx) CT, is used for the planned beam path. The angular variation and discordance between the PET- and marker-defined paths were derived to investigate the intrafraction prostate motion. For studies with large discordance, the relative location between the centroid and pelvic bones seen in the post-Tx CT was examined. The PET/CT studies are categorized for distinguishing the prostate motion that occurred before or after beam delivery. The post-PET CT was acquired after PET imaging to investigate prostate motion due to physiological changes during the extended PET acquisition. Results: The less than 2 deg. of angular variation indicates that the patient roll was minimal within the immobilization device. Thirty of the 50 studies with small discordance, referred as good cases, show a consistent alignment between the field edges and the positron emission distributions from the entrance to the distal edge. For those good cases, average displacements are 0.6 and 1.3 mm along the anterior-posterior (D{sub AP}) and superior-inferior (D{sub SI}) directions, respectively, with 1.6 mm standard deviations in both directions. For the remaining 20 studies demonstrating a large discordance (more than 6 mm in either D{sub AP} or D{sub SI}), 13

  19. Concurrent Diffuse Pyelonephritis and Prostatitis: Discordant Findings on Sequential FDG PET/CT and 67Ga SPECT/CT Imaging.

    PubMed

    Lucaj, Robert; Achong, Dwight M

    2017-01-01

    A 45-year-old man underwent FDG PET/CT for initial imaging evaluation of recurrent Escherichia coli urinary tract infections, which demonstrated no significant FDG uptake in either kidney and subtle FDG uptake in the right prostate lobe. Subsequent Ga SPECT/CT demonstrated abnormal intense gallium uptake throughout the right kidney and entire prostate gland, clearly discordant with PET/CT findings and consistent with unexpected concurrent pyelonephritis and prostatitis. Although FDG has effectively replaced Ga in everyday clinical practice, the current case serves as a reminder that there is still a role for Ga in the evaluation of genitourinary infections.

  20. FDG PET/CT images demonstrating Fournier gangrene with bilateral pelvic muscle extension in a patient with recurrent rectosigmoid cancer.

    PubMed

    Hsu, Chia-Tien; Kao, Pan-Fu; Huang, Chi-Chou; Huang, Hsin-Hui; Lee, Jong-Kang

    2014-01-01

    A 71-year-old male patient with Parkinsonism was referred for an F-FDG PET/CT scan for suspicious recurrence of rectosigmoid adenocarcinoma. The FDG PET/CT scan revealed increased FDG uptakes in the lower pelvic region around the wall of the rectal stump, with extension to the bilateral pelvic sidewalls and the right gluteous minimus muscle. In addition, multiple small air bubbles were noted in the lesions on the attenuation CT images. Fournier gangrene was diagnosed. After treatment with intravenous antibiotics and debridement with sigmoidoscopic irrigation, the patient was discharged and remained uneventful during clinical follow-up for 50 days.

  1. Optimization of oncological {sup 18}F-FDG PET/CT imaging based on a multiparameter analysis

    SciTech Connect

    Menezes, Vinicius O.; D’Errico, Francesco; Namías, Mauro; Larocca, Ticiana F.; Soares, Milena B. P.

    2016-02-15

    Purpose: This paper describes a method to achieve consistent clinical image quality in {sup 18}F-FDG scans accounting for patient habitus, dose regimen, image acquisition, and processing techniques. Methods: Oncological PET/CT scan data for 58 subjects were evaluated retrospectively to derive analytical curves that predict image quality. Patient noise equivalent count rate and coefficient of variation (CV) were used as metrics in their analysis. Optimized acquisition protocols were identified and prospectively applied to 179 subjects. Results: The adoption of different schemes for three body mass ranges (<60 kg, 60–90 kg, >90 kg) allows improved image quality with both point spread function and ordered-subsets expectation maximization-3D reconstruction methods. The application of this methodology showed that CV improved significantly (p < 0.0001) in clinical practice. Conclusions: Consistent oncological PET/CT image quality on a high-performance scanner was achieved from an analysis of the relations existing between dose regimen, patient habitus, acquisition, and processing techniques. The proposed methodology may be used by PET/CT centers to develop protocols to standardize PET/CT imaging procedures and achieve better patient management and cost-effective operations.

  2. Advances in image-guided radiation therapy-the role of PET-CT

    SciTech Connect

    Heron, Dwight E. . E-mail: heronD2@upmc.edu; Smith, Ryan P.; Andrade, Regiane S.

    2006-04-01

    In the era of image-guided radiation therapy (IGRT), the greatest challenge remains target delineation, as the opportunity to maximize cures while simultaneously decreasing radiation dose to the surrounding normal tissues is to be realized. Over the last 2 decades, technological advances in radiographic imaging, biochemistry, and molecular biology have played an increasing role in radiation treatment planning, delivery, and evaluation of response. Previously, fluoroscopy formed the basis of radiation treatment planning. Beginning in the late 1980s, computed tomography (CT) has become the basis for modern radiation treatment planning and delivery, coincident with the rise of 3-dimensional conformal radiation therapy (3DCRT). Additionally, multi-modality anatomic imaging registration was the solution pursued to augment delineation of tumors and surrounding structures on CT-based treatment planning. Although these imaging modalities provide the customary anatomic details necessary for radiation treatment planning, they have limitations, including difficulty with identification of small tumor deposits, tumor extension, and distinction from scar tissues. To overcome these limitations, PET and, more recently, PET-CT have been innovative regarding the extent of disease appraisal, target delineation in the treatment planning, and assessment of therapy response. We review the role of functional imaging in IGRT as it reassures transformations on the field of radiation oncology. As we move toward the era of IGRT, the use of multi-modality imaging fusion, and the introduction of more sensitive and specific PET-CT tracers may further assist target definition. Furthermore, the potential to predict early outcome or even detect early recurrence of tumor, may allow for the tailoring of intervention in cancer patients. The convergence of a biological target volume, and perhaps multi-tracer tumor, molecular, and genetic profile tumors will probably be vital in cancer treatment

  3. Automated detection of lung tumors in PET/CT images using active contour filter

    NASA Astrophysics Data System (ADS)

    Teramoto, Atsushi; Adachi, Hayato; Tsujimoto, Masakazu; Fujita, Hiroshi; Takahashi, Katsuaki; Yamamuro, Osamu; Tamaki, Tsuneo; Nishio, Masami; Kobayashi, Toshiki

    2015-03-01

    In a previous study, we developed a hybrid tumor detection method that used both computed tomography (CT) and positron emission tomography (PET) images. However, similar to existing computer-aided detection (CAD) schemes, it was difficult to detect low-contrast lesions that touch to the normal organs such as the chest wall or blood vessels in the lung. In the current study, we proposed a novel lung tumor detection method that uses active contour filters to detect the nodules deemed "difficult" in previous CAD schemes. The proposed scheme detects lung tumors using both CT and PET images. As for the detection in CT images, the massive region was first enhanced using an active contour filter (ACF), which is a type of contrast enhancement filter that has a deformable kernel shape. The kernel shape involves closed curves that are connected by several nodes that move iteratively in order to enclose the massive region. The final output of ACF is the difference between the maximum pixel value on the deformable kernel, and pixel value on the center of the filter kernel. Subsequently, the PET images were binarized to detect the regions of increased uptake. The results were integrated, followed by the false positive reduction using 21 characteristic features and three support vector machines. In the experiment, we evaluated the proposed method using 100 PET/CT images. More than half of nodules missed using previous methods were accurately detected. The results indicate that our method may be useful for the detection of lung tumors using PET/CT images.

  4. (68)Ga-PSMA PET/CT: Joint EANM and SNMMI procedure guideline for prostate cancer imaging: version 1.0.

    PubMed

    Fendler, Wolfgang P; Eiber, Matthias; Beheshti, Mohsen; Bomanji, Jamshed; Ceci, Francesco; Cho, Steven; Giesel, Frederik; Haberkorn, Uwe; Hope, Thomas A; Kopka, Klaus; Krause, Bernd J; Mottaghy, Felix M; Schöder, Heiko; Sunderland, John; Wan, Simon; Wester, Hans-Jürgen; Fanti, Stefano; Herrmann, Ken

    2017-03-10

    The aim of this guideline is to provide standards for the recommendation, performance, interpretation and reporting of (68)Ga-PSMA PET/CT for prostate cancer imaging. These recommendations will help to improve accuracy, precision, and repeatability of (68)Ga-PSMA PET/CT for prostate cancer essentially needed for implementation of this modality in science and routine clinical practice.

  5. A software tool for stitching two PET/CT body segments into a single whole-body image set.

    PubMed

    Chang, Tingting; Chang, Guoping; Clark, John W; Rohren, Eric M; Mawlawi, Osama R

    2012-05-10

    A whole-body PET/CT scan extending from the vertex of the head to the toes of the patient is not feasible on a number of commercially available PET/CT scanners due to a limitation in the extent of bed travel on these systems. In such cases, the PET scan has to be divided into two parts: one covering the upper body segment, while the other covering the lower body segment. The aim of this paper is to describe and evaluate, using phantom and patient studies, a software tool that was developed to stitch two body segments and output a single whole-body image set, thereby facilitating the interpretation of whole-body PET scans. A mathematical model was first developed to stitch images from two body segments using three landmarks. The model calculates the relative positions of the landmarks on the two segments and then generates a rigid transformation that aligns these landmarks on the two segments. A software tool was written to implement this model while correcting for radioactive decay between the two body segments, and output a single DICOM whole-body image set with all the necessary tags. One phantom, and six patient studies were conducted to evaluate the performance of the software. In these studies, six radio-opaque markers (BBs) were used as landmarks (three on each leg). All studies were acquired in two body segments with BBs placed in the overlap region of the two segments. The PET/CT images of each segment were then stitched using the software tool to create a single DICOM whole-body PET/CT image. Evaluation of the stitching tool was based on visual inspection, consistency of radiotracer uptake in the two segments, and ability to display the resultant DICOM image set on two independent workstations. The software tool successfully stitched the two segments of the phantom image, and generated a single whole-body DICOM PET/CT image set that had the correct alignment and activity concentration throughout the image. The stitched images were viewed by two independent

  6. Real-time volume rendering visualization of dual-modality PET/CT images with interactive fuzzy thresholding segmentation.

    PubMed

    Kim, Jinman; Cai, Weidong; Eberl, Stefan; Feng, Dagan

    2007-03-01

    Three-dimensional (3-D) visualization has become an essential part for imaging applications, including image-guided surgery, radiotherapy planning, and computer-aided diagnosis. In the visualization of dual-modality positron emission tomography and computed tomography (PET/CT), 3-D volume rendering is often limited to rendering of a single image volume and by high computational demand. Furthermore, incorporation of segmentation in volume rendering is usually restricted to visualizing the presegmented volumes of interest. In this paper, we investigated the integration of interactive segmentation into real-time volume rendering of dual-modality PET/CT images. We present and validate a fuzzy thresholding segmentation technique based on fuzzy cluster analysis, which allows interactive and real-time optimization of the segmentation results. This technique is then incorporated into a real-time multi-volume rendering of PET/CT images. Our method allows a real-time fusion and interchangeability of segmentation volume with PET or CT volumes, as well as the usual fusion of PET/CT volumes. Volume manipulations such as window level adjustments and lookup table can be applied to individual volumes, which are then fused together in real time as adjustments are made. We demonstrate the benefit of our method in integrating segmentation with volume rendering in its application to PET/CT images. Responsive frame rates are achieved by utilizing a texture-based volume rendering algorithm and the rapid transfer capability of the high-memory bandwidth available in low-cost graphic hardware.

  7. Multiple myeloma: 18F-FDG-PET/CT and diagnostic imaging.

    PubMed

    Mihailovic, Jasna; Goldsmith, Stanley J

    2015-01-01

    Multiple myeloma (MM) is a relatively rare hematologic disorder characterized by proliferation of plasma cells, primarily involving the bone marrow. Extramedullary involvement also occurs with poor prognosis. Asymptomatic plasma cell disorders, monoclonal gammopathy of uncertain significance, and smoldering MM, which do not require therapy, should be distinguished from symptomatic MM, which requires treatment. MM may present with CRAB, elevated Calcium levels, Renal insufficiency, Anemia, and Bone lesions (including lytic lesions and osteopenia), as well as elevated levels of serum M protein or urine M protein or both. Nonsecretory myeloma in which serum and urine M proteins are absent occurs rarely, accounting for 1%-5% of patients with myeloma, but low levels of abnormal immunoglobulins are often present. Staging of patients with MM is done according to the Durie and Salmon criteria based on laboratory testing (determination of hemoglobin, serum calcium, and serum and urine M proteins) and conventional radiography. A variety of diagnostic imaging procedures have been employed to assess the extent of disease in MM and to evaluate the response to treatment as well as provide surveillance for the detection of recurrent disease. These include whole-body x-ray, which despite its limitations is regularly used to detect lytic bone lesions; CT radiography; MRI; and a variety of radionuclide imaging procedures, with (18)F-FDG-PET/CT emerging as the radionuclide procedure of choice. Recently, the Durie-Salmon criteria have been upgrade to the Durie-Salmon PLUS system, which includes (18)F-FDG-PET/CT and MRI of the spine and pelvis.

  8. Summary of the UPICT Protocol for 18F-FDG PET/CT Imaging in Oncology Clinical Trials

    PubMed Central

    Graham, Michael M.; Wahl, Richard L.; Hoffman, John M.; Yap, Jeffrey T.; Sunderland, John J.; Boellaard, Ronald; Perlman, Eric S.; Kinahan, Paul E.; Christian, Paul E.; Hoekstra, Otto S.; Dorfman, Gary S.

    2015-01-01

    The Uniform Protocols for Imaging in Clinical Trials (UPICT) 18F-FDG PET/CT protocol is intended to guide the performance of whole-body FDG PET/CT studies within the context of single- and multiple-center clinical trials of oncologic therapies by providing acceptable (minimum), target, and ideal standards for all phases of imaging. The aim is to minimize variability in intra- and intersubject, intra- and inter-platform, interexamination, and interinstitutional primary or derived data. The goal of this condensed version of the much larger document is to make readers aware of the general content and subject area. The document has several main subjects: context of the imaging protocol within the clinical trial; site selection, qualification, and training; subject scheduling; subject preparation; imaging-related substance preparation and administration; imaging procedure; image postprocessing; image analysis; image interpretation; archiving and distribution of data; quality control; and imaging-associated risks and risk management. PMID:25883122

  9. Summary of the UPICT Protocol for 18F-FDG PET/CT Imaging in Oncology Clinical Trials.

    PubMed

    Graham, Michael M; Wahl, Richard L; Hoffman, John M; Yap, Jeffrey T; Sunderland, John J; Boellaard, Ronald; Perlman, Eric S; Kinahan, Paul E; Christian, Paul E; Hoekstra, Otto S; Dorfman, Gary S

    2015-06-01

    The Uniform Protocols for Imaging in Clinical Trials (UPICT) (18)F-FDG PET/CT protocol is intended to guide the performance of whole-body FDG PET/CT studies within the context of single- and multiple-center clinical trials of oncologic therapies by providing acceptable (minimum), target, and ideal standards for all phases of imaging. The aim is to minimize variability in intra- and intersubject, intra- and interplatform, interexamination, and interinstitutional primary or derived data. The goal of this condensed version of the much larger document is to make readers aware of the general content and subject area. The document has several main subjects: context of the imaging protocol within the clinical trial; site selection, qualification, and training; subject scheduling; subject preparation; imaging-related substance preparation and administration; imaging procedure; image postprocessing; image analysis; image interpretation; archiving and distribution of data; quality control; and imaging-associated risks and risk management.

  10. Automated liver segmentation for whole-body low-contrast CT images from PET-CT scanners.

    PubMed

    Wang, Xiuying; Li, Changyang; Eberl, Stefan; Fulham, Michael; Feng, Dagan

    2009-01-01

    Accurate objective automated liver segmentation in PET-CT studies is important to improve the identification and localization of hepatic tumor. However, this segmentation is an extremely challenging task from the low-contrast CT images captured from PET-CT scanners because of the intensity similarity between liver and adjacent loops of bowel, stomach and muscle. In this paper, we propose a novel automated three-stage liver segmentation technique for PET-CT whole body studies, where: 1) the starting liver slice is automatically localized based on the liver - lung relations; 2) the "masking" slice containing the biggest liver section is localized using the ratio of liver ROI size to the right half of abdomen ROI size; 3) the liver segmented from the "masking" slice forms the initial estimation or mask for the automated liver segmentation. Our experimental results from clinical PET-CT studies show that this method can automatically segment the liver for a range of different patients, with consistent objective selection criteria and reproducible accurate results.

  11. Intraobserver and Interobserver Variability in GTV Delineation on FDG-PET-CT Images of Head and Neck Cancers

    SciTech Connect

    Breen, Stephen L. |. E-mail: Stephen.Breen@rmp.uhn.on.ca; Publicover, Julia; De Silva, Shiroma; Pond, Greg; Brock, Kristy |; O'Sullivan, Brian |; Cummings, Bernard; Dawson, Laura; Kim, John; Ringash, Jolie; Waldron, John |; Keller, Anne |; Yu, Eugene; Hendler, Aaron |

    2007-07-01

    Purpose: To determine if the addition of fluorodeoxyglucose positron emission tomography (FDG-PET) data changes primary site gross tumor volumes (GTVs) in head and neck cancers. Methods and Materials: Computed tomography (CT), contrast-enhanced CT, and FDG-PET-CT scans were obtained in 10 patients with head and neck cancers. Eight experienced observers (6 head and neck oncologists and 2 neuro-radiologists) with access to clinical and radiologic reports outlined primary site GTVs on each modality. Three cases were recontoured twice to assess intraobserver variability. The magnitudes of the GTVs were compared. Intra- and interobserver variability was assessed by a two-way repeated measures analysis of variance. Inter- and intraobserver reliability were calculated. Results: There were no significant differences in the GTVs across the image modalities when compared as ensemble averages; the Wilcoxon matched-pairs signed-rank test showed that CT volumes were larger than PET-CT. Observers demonstrated the greatest consistency and were most interchangeable on contrast-enhanced CT; they performed less reliably on PET-CT. Conclusions: The addition of PET-CT to primary site GTV delineation of head and neck cancers does not change the volume of the GTV defined by this group of expert observers in this patient sample. An FDG-PET may demonstrate differences in neck node delineation and in other disease sites.

  12. PET/CT (and CT) instrumentation, image reconstruction and data transfer for radiotherapy planning.

    PubMed

    Sattler, Bernhard; Lee, John A; Lonsdale, Markus; Coche, Emmanuel

    2010-09-01

    The positron emission tomography in combination with CT in hybrid, cross-modality imaging systems (PET/CT) gains more and more importance as a part of the treatment-planning procedure in radiotherapy. Positron emission tomography (PET), as a integral part of nuclear medicine imaging and non-invasive imaging technique, offers the visualization and quantification of pre-selected tracer metabolism. In combination with the structural information from CT, this molecular imaging technique has great potential to support and improve the outcome of the treatment-planning procedure prior to radiotherapy. By the choice of the PET-Tracer, a variety of different metabolic processes can be visualized. First and foremost, this is the glucose metabolism of a tissue as well as for instance hypoxia or cell proliferation. This paper comprises the system characteristics of hybrid PET/CT systems. Acquisition and processing protocols are described in general and modifications to cope with the special needs in radiooncology. This starts with the different position of the patient on a special table top, continues with the use of the same fixation material as used for positioning of the patient in radiooncology while simulation and irradiation and leads to special processing protocols that include the delineation of the volumes that are subject to treatment planning and irradiation (PTV, GTV, CTV, etc.). General CT acquisition and processing parameters as well as the use of contrast enhancement of the CT are described. The possible risks and pitfalls the investigator could face during the hybrid-imaging procedure are explained and listed. The interdisciplinary use of different imaging modalities implies a increase of the volume of data created. These data need to be stored and communicated fast, safe and correct. Therefore, the DICOM-Standard provides objects and classes for this purpose (DICOM RT). Furthermore, the standard DICOM objects and classes for nuclear medicine (NM, PT) and

  13. Improved correction for the tissue fraction effect in lung PET/CT imaging

    NASA Astrophysics Data System (ADS)

    Holman, Beverley F.; Cuplov, Vesna; Millner, Lynn; Hutton, Brian F.; Maher, Toby M.; Groves, Ashley M.; Thielemans, Kris

    2015-09-01

    Recently, there has been an increased interest in imaging different pulmonary disorders using PET techniques. Previous work has shown, for static PET/CT, that air content in the lung influences reconstructed image values and that it is vital to correct for this ‘tissue fraction effect’ (TFE). In this paper, we extend this work to include the blood component and also investigate the TFE in dynamic imaging. CT imaging and PET kinetic modelling are used to determine fractional air and blood voxel volumes in six patients with idiopathic pulmonary fibrosis. These values are used to illustrate best and worst case scenarios when interpreting images without correcting for the TFE. In addition, the fractional volumes were used to determine correction factors for the SUV and the kinetic parameters. These were then applied to the patient images. The kinetic parameters K1 and Ki along with the static parameter SUV were all found to be affected by the TFE with both air and blood providing a significant contribution to the errors. Without corrections, errors range from 34-80% in the best case and 29-96% in the worst case. In the patient data, without correcting for the TFE, regions of high density (fibrosis) appeared to have a higher uptake than lower density (normal appearing tissue), however this was reversed after air and blood correction. The proposed correction methods are vital for quantitative and relative accuracy. Without these corrections, images may be misinterpreted.

  14. Automatic lung tumor segmentation on PET/CT images using fuzzy Markov random field model.

    PubMed

    Guo, Yu; Feng, Yuanming; Sun, Jian; Zhang, Ning; Lin, Wang; Sa, Yu; Wang, Ping

    2014-01-01

    The combination of positron emission tomography (PET) and CT images provides complementary functional and anatomical information of human tissues and it has been used for better tumor volume definition of lung cancer. This paper proposed a robust method for automatic lung tumor segmentation on PET/CT images. The new method is based on fuzzy Markov random field (MRF) model. The combination of PET and CT image information is achieved by using a proper joint posterior probability distribution of observed features in the fuzzy MRF model which performs better than the commonly used Gaussian joint distribution. In this study, the PET and CT simulation images of 7 non-small cell lung cancer (NSCLC) patients were used to evaluate the proposed method. Tumor segmentations with the proposed method and manual method by an experienced radiation oncologist on the fused images were performed, respectively. Segmentation results obtained with the two methods were similar and Dice's similarity coefficient (DSC) was 0.85 ± 0.013. It has been shown that effective and automatic segmentations can be achieved with this method for lung tumors which locate near other organs with similar intensities in PET and CT images, such as when the tumors extend into chest wall or mediastinum.

  15. Automatic Lung Tumor Segmentation on PET/CT Images Using Fuzzy Markov Random Field Model

    PubMed Central

    Guo, Yu; Feng, Yuanming; Sun, Jian; Lin, Wang; Sa, Yu; Wang, Ping

    2014-01-01

    The combination of positron emission tomography (PET) and CT images provides complementary functional and anatomical information of human tissues and it has been used for better tumor volume definition of lung cancer. This paper proposed a robust method for automatic lung tumor segmentation on PET/CT images. The new method is based on fuzzy Markov random field (MRF) model. The combination of PET and CT image information is achieved by using a proper joint posterior probability distribution of observed features in the fuzzy MRF model which performs better than the commonly used Gaussian joint distribution. In this study, the PET and CT simulation images of 7 non-small cell lung cancer (NSCLC) patients were used to evaluate the proposed method. Tumor segmentations with the proposed method and manual method by an experienced radiation oncologist on the fused images were performed, respectively. Segmentation results obtained with the two methods were similar and Dice's similarity coefficient (DSC) was 0.85 ± 0.013. It has been shown that effective and automatic segmentations can be achieved with this method for lung tumors which locate near other organs with similar intensities in PET and CT images, such as when the tumors extend into chest wall or mediastinum. PMID:24987451

  16. PET/CT in radiation oncology

    SciTech Connect

    Pan, Tinsu; Mawlawi, Osama

    2008-11-15

    PET/CT is an effective tool for the diagnosis, staging and restaging of cancer patients. It combines the complementary information of functional PET images and anatomical CT images in one imaging session. Conventional stand-alone PET has been replaced by PET/CT for improved patient comfort, patient throughput, and most importantly the proven clinical outcome of PET/CT over that of PET and that of separate PET and CT. There are over two thousand PET/CT scanners installed worldwide since 2001. Oncology is the main application for PET/CT. Fluorine-18 deoxyglucose is the choice of radiopharmaceutical in PET for imaging the glucose uptake in tissues, correlated with an increased rate of glycolysis in many tumor cells. New molecular targeted agents are being developed to improve the accuracy of targeting different disease states and assessing therapeutic response. Over 50% of cancer patients receive radiation therapy (RT) in the course of their disease treatment. Clinical data have demonstrated that the information provided by PET/CT often changes patient management of the patient and/or modifies the RT plan from conventional CT simulation. The application of PET/CT in RT is growing and will become increasingly important. Continuing improvement of PET/CT instrumentation will also make it easier for radiation oncologists to integrate PET/CT in RT. The purpose of this article is to provide a review of the current PET/CT technology, to project the future development of PET and CT for PET/CT, and to discuss some issues in adopting PET/CT in RT and potential improvements in PET/CT simulation of the thorax in radiation therapy.

  17. Targeted Molecular Imaging in Adrenal Disease—An Emerging Role for Metomidate PET-CT

    PubMed Central

    Mendichovszky, Iosif A.; Powlson, Andrew S.; Manavaki, Roido; Aigbirhio, Franklin I.; Cheow, Heok; Buscombe, John R.; Gurnell, Mark; Gilbert, Fiona J.

    2016-01-01

    Adrenal lesions present a significant diagnostic burden for both radiologists and endocrinologists, especially with the increasing number of adrenal ‘incidentalomas’ detected on modern computed tomography (CT) or magnetic resonance imaging (MRI). A key objective is the reliable distinction of benign disease from either primary adrenal malignancy (e.g., adrenocortical carcinoma or malignant forms of pheochromocytoma/paraganglioma (PPGL)) or metastases (e.g., bronchial, renal). Benign lesions may still be associated with adverse sequelae through autonomous hormone hypersecretion (e.g., primary aldosteronism, Cushing’s syndrome, phaeochromocytoma). Here, identifying a causative lesion, or lateralising the disease to a single adrenal gland, is key to effective management, as unilateral adrenalectomy may offer the potential for curing conditions that are typically associated with significant excess morbidity and mortality. This review considers the evolving role of positron emission tomography (PET) imaging in addressing the limitations of traditional cross-sectional imaging and adjunctive techniques, such as venous sampling, in the management of adrenal disorders. We review the development of targeted molecular imaging to the adrenocortical enzymes CYP11B1 and CYP11B2 with different radiolabeled metomidate compounds. Particular consideration is given to iodo-metomidate PET tracers for the diagnosis and management of adrenocortical carcinoma, and the increasingly recognized utility of 11C-metomidate PET-CT in primary aldosteronism. PMID:27869719

  18. Graph cut based co-segmentation of lung tumor in PET-CT images

    NASA Astrophysics Data System (ADS)

    Ju, Wei; Xiang, Dehui; Zhang, Bin; Chen, Xinjian

    2015-03-01

    Accurate segmentation of pulmonary tumor is important for clinicians to make appropriate diagnosis and treatment. Positron Emission Tomography (PET) and Computed Tomography (CT) are two commonly used imaging technologies for image-guided radiation therapy. In this study, we present a graph-based method to integrate the two modalities to segment the tumor simultaneously on PET and CT images. The co-segmentation problem is formulated as an energy minimization problem. Two weighted sub-graphs are constructed for PET and CT. The characteristic information of the two modalities is encoded on the edges of the graph. A context cost is enforced by adding context arcs to achieve consistent results between the two modalities. An optimal solution can be achieved by solving a maximum flow problem. The proposed segmentation method was validated on 18 sets of PET-CT images from different patients with non-small cell lung cancer (NSCLC). The quantitative results show significant improvement of our method with a mean DSC value 0.82.

  19. 18F-FDG PET/CT/MRI Fusion Images Showing Cranial and Peripheral Nerve Involvement in Neurolymphomatosis

    PubMed Central

    Trevisan, Ana Carolina; Ribeiro, Fernanda Borges; Itikawa, Emerson Nobuyuki; Alexandre, Leonardo Santos; Pitella, Felipe Arriva; Santos, Antonio Carlos; Simões, Belinda Pinto; Wichert-Ana, Lauro

    2017-01-01

    We report a 56-year-old female patient with non-Hodgkin's diffuse large B cell lymphoma (NHL) who, on magnetic resonance imaging (MRI) with a T1 weighted and gadolinium-enhanced imaging, was found to have thickening and infiltration in 75% of peripheral nerves of the patient and enlargements of cranial nerves, possibly related to lymphomatous infiltration. Subsequent positron emission tomography/computed tomography (PET/CT) using 18F-labeled 2-deoxy-2-fluoro-d-glucose (18F-FDG) showed widespread active involvement of the cervical plexus, bilateral peripheral nerves, right femoral nerve, the parasellar region of the skull, and marked hypermetabolism in the left trigeminal ganglia. This case re-emphasizes that while CT and MRI provide anatomical details, 18F-FDG PET/CT images better delineate the metabolic activity of neurolymphomatosis (NL) in the peripheral and central nervous system. PMID:28242998

  20. Method for transforming CT images for attenuation correction in PET/CT imaging

    SciTech Connect

    Carney, Jonathan P.J.; Townsend, David W.; Rappoport, Vitaliy; Bendriem, Bernard

    2006-04-15

    A tube-voltage-dependent scheme is presented for transforming Hounsfield units (HU) measured by different computed tomography (CT) scanners at different x-ray tube voltages (kVp) to 511 keV linear attenuation values for attenuation correction in positron emission tomography (PET) data reconstruction. A Gammex 467 electron density CT phantom was imaged using a Siemens Sensation 16-slice CT, a Siemens Emotion 6-slice CT, a GE Lightspeed 16-slice CT, a Hitachi CXR 4-slice CT, and a Toshiba Aquilion 16-slice CT at kVp ranging from 80 to 140 kVp. All of these CT scanners are also available in combination with a PET scanner as a PET/CT tomograph. HU obtained for various reference tissue substitutes in the phantom were compared with the known linear attenuation values at 511 keV. The transformation, appropriate for lung, soft tissue, and bone, yields the function 9.6x10{sup -5}{center_dot}(HU+1000) below a threshold of {approx}50 HU and a{center_dot}(HU+1000)+b above the threshold, where a and b are fixed parameters that depend on the kVp setting. The use of the kVp-dependent scaling procedure leads to a significant improvement in reconstructed PET activity levels in phantom measurements, resolving errors of almost 40% otherwise seen for the case of dense bone phantoms at 80 kVp. Results are also presented for patient studies involving multiple CT scans at different kVp settings, which should all lead to the same 511 keV linear attenuation values. A linear fit to values obtained from 140 kVp CT images using the kVp-dependent scaling plotted as a function of the corresponding values obtained from 80 kVp CT images yielded y=1.003x-0.001 with an R{sup 2} value of 0.999, indicating that the same values are obtained to a high degree of accuracy.

  1. Evaluation of 68Ga-Labeled MG7 Antibody: A Targeted Probe for PET/CT Imaging of Gastric Cancer

    PubMed Central

    Xu, Bing; Li, Xiaowei; Yin, Jipeng; Liang, Cong; Liu, Lijuan; Qiu, Zhaoyan; Yao, Liping; Nie, Yongzhan; Wang, Jing; Wu, Kaichun

    2015-01-01

    MG7-Ag, a specific gastric cancer-associated antigen, can be used to non-invasively monitor gastric cancer by molecular imaging with positron emission tomography/computed tomography (PET/CT). In this study, we prepared and evaluated a 68Ga-labeled MG7 antibody as a molecular probe for nanoPET/CT imaging of gastric cancer in a BGC-823 tumor xenografted mouse model. Macrocyclic chelator 1,4,7-triazacyclononane-N,N0,N00-triacetic acid (NOTA)-conjugated MG7 antibody was synthesized and radiolabeled with 68Ga (t1/2 = 67.71 min). Then, 68Ga-NOTA-MG7 was tested using in vitro cytological studies, in vivo nanoPET/CT and Cerenkov imaging studies as well as ex vivo biodistribution and histology studies. The in vitro experiments demonstrated that 68Ga-NOTA-MG7 has an excellent radiolabeling efficiency of approximately 99% without purification, and it is stable in serum after 120 min of incubation. Cell uptake and retention studies confirmed that 68Ga-NOTA-MG7 has good binding affinity and tumor cell retention. For the nanoPET imaging study, the predominant uptake of 68Ga-NOTA-MG7 was visualized in tumor, liver and kidneys. The tumor uptake reached at its peak (2.53 ± 0.28%ID/g) at 60 min pi. Cherenkov imaging also confirmed the specificity of tumor uptake. Moreover, the biodistribution results were consistent with the quantification data of nanoPET/CT imaging. Histologic analysis also demonstrated specific staining of BGC-823 tumor cell lines. PMID:25733152

  2. Quantitative outcome of registration methods for correcting cardiac drift in cardiac PET/CT imaging.

    PubMed

    Nye, Jonathan A; Tudorascu, Dana; Esteves, Fabio; Votaw, John R

    2016-03-08

    Myocardial perfusion studies suffer from artifacts caused by misalignment of the transmission and emission data due to the influences of voluntary and involuntary patient motion. Regardless of 68Ge or respiratory-averaged CT based attenuation correction and good patient cooperation, approximately 21% of perfusion studies exhibit artifacts arising from misalignment that cannot be corrected by manipulating the attenuation acquisition protocol. This misalignment, termed cardiac drift, is caused by slow-moving abdominal cavity contents that reposition the heart in the thorax and appear as myocardial uptake overlying the left CT lung in fused PET/CT images. This study evaluates three postimaging registration techniques to correct PET/CT misalignment by altering the transmission map to match myo-cardial uptake. Simulated misalignment studies were performed with a cardiac torso phantom filled with [18F]FDG at 10:1 myocardium/background. An air-filled saline bag affixed to the medial left lung surface served as a distensible lung. An initial CT acquisition was followed by successive PET acquisitions consisting of small displacements of the cardiac insert into the left lung. Phantom transmission scans were aligned to the myocardial uptake in the emission scans by applying 1) full rigid-body translations and rotations, 2) rigid-body restricted to medial / lateral and superior / inferior translation, or 3) an emission-driven method that adds myocardial tissue to the transmission scan. These methods were also applied to 10 low-likelihood coronary artery disease (CAD) patients showing signs of cardiac drift. Full rigid-body registration showed significant over-correction (p < 0.004) of activity concentrations in the artifact areas of the phantom data due the relocation of highly attenuating structures (i.e., spine). Inaccurate regional activity distributions were also observed as streaks extending from the spine and these results were replicated in the patient population. There

  3. Quantitative outcome of registration methods for correcting cardiac drift in cardiac PET/CT imaging.

    PubMed

    Nye, Jonathon A; Tudorascu, Dana; Esteves, Fabio; Votaw, John R

    2016-03-01

    Myocardial perfusion studies suffer from artifacts caused by misalignment of the transmission and emission data due to the influences of voluntary and involuntary patient motion. Regardless of G68e or respiratory-averaged CT based attenuation correction and good patient cooperation, approximately 21% of perfusion studies exhibit artifacts arising from misalignment that cannot be corrected by manipulating the attenuation acquisition protocol. This misalignment, termed cardiac drift, is caused by slow-moving abdominal cavity contents that reposition the heart in the thorax and appear as myocardial uptake overlying the left CT lung in fused PET/CT images. This study evaluates three postimaging registration techniques to correct PET/CT misalignment by altering the transmission map to match myocardial uptake. Simulated misalignment studies were performed with a cardiac torso phantom filled with [F18]FDG at 10:1 myocardium/background. An air-filled saline bag affixed to the medial left lung surface served as a distensible lung. An initial CT acquisition was followed by successive PET acquisitions consisting of small displacements of the cardiac insert into the left lung. Phantom transmission scans were aligned to the myocardial uptake in the emission scans by applying 1) full rigid-body translations and rotations, 2) rigid-body restricted to medial / lateral and superior / inferior translation, or 3) an emission-driven method that adds myocardial tissue to the transmission scan. These methods were also applied to 10 low-likelihood coronary artery disease (CAD) patients showing signs of cardiac drift. Full rigid-body registration showed significant over-correction (p<0.004) of activity concentrations in the artifact areas of the phantom data due the relocation of highly attenuating structures (i.e., spine). Inaccurate regional activity distributions were also observed as streaks extending from the spine and these results were replicated in the patient population. There

  4. Crossed Cerebellar Diaschisis: Three Case Reports Imaging Using a Tri-Modality PET/CT-MR System.

    PubMed

    Han, Shuguang; Wang, Xiaopeng; Xu, Kai; Hu, Chunfeng

    2016-01-01

    Crossed cerebellar diaschisis (CCD) describes a depression of oxidative metabolism glucose and blood flow in the cerebellum secondary to a supratentorial lesion in the contralateral cerebral hemisphere. PET/MR has the potential to become a powerful tool for demonstrating and imaging intracranial lesions .We herein report 3 cases of CCD imaging using a tri-modality PET/CT-MR set-up for investigating the value of adding MRI rather than CT to PET in clinical routine.We describe 3 patients with CCD and neurological symptoms in conjunction with abnormal cerebral fluorodeoxyglucose (FDG) positron emission tomography/computed tomography-magnetic resonance imaging (PET/CT-MR) manifestations including arterial spin-labeling (ASL) and T2-weighted images. In all, 18FDG-PET/CT detected positive FDG uptake in supratentorial lesions, and hypometabolism with atrophy in the contralateral cerebellum. More than that, hybrid PET/MRI provided a more accurate anatomic localization and ASL indicated disruption of the cortico-ponto-cerebellar pathway.Using pathology or long-term clinical follow-up to confirm the PET and ASL findings, the supratentorial lesions of the 3 patients were respectively diagnosed with cerebral infarction, recurrent glioma, and metastasis.The reports emphasize the significance of multimodality radiological examinations. Multimodality imaging contributes to proper diagnosis, management, and follow-up of supratentorial lesions with CCD.

  5. PET/CT imaging of human somatostatin receptor 2 (hsstr2) as reporter gene for gene therapy

    NASA Astrophysics Data System (ADS)

    Hofmann, M.; Gazdhar, A.; Weitzel, T.; Schmid, R.; Krause, T.

    2006-12-01

    Localized information on region-selective gene expression in small animals is widely obtained by use of reporter genes inducing light emission. Using these reporter genes for imaging deep inside the human body fluorescent probes are hindered by attenuation, scattering and possible fluorescence quenching. This can be overcome by use of radio-peptide receptors as reporter genes. Therefore, the feasibility of the somatostatin receptor 2 expression vector system for expression imaging was checked against a control vector containing luciferase gene. For in vivo transduction of vector DNA into the rat forelimb muscles the in vivo electroporation technique was chosen because of its high regio-selectivity. The gene expression was imaged by high-sensitive CCD camera (luciferase activity) and by PET/CT using a Ga-68-DOTATOC as radio peptide probe. The relative sstr2 expression was enhanced by gene transduction at maximum to a factor of 15. The PET/CT images could be fully quantified. The above demonstrated feasibility of radio-peptide PET/CT reporter gene imaging may serve in the future as a tool for full quantitative understanding of regional gene expression, especially in large animals and humans.

  6. [Quality control of the research on mechanisms of acupuncture therapy by using PET-CT imaging techniques].

    PubMed

    Liu, Mai-lan; Lan, Lei; Zeng, Fang; Li, Xue-zhi; Liu, Xu-guang; Liang, Fan-rong

    2010-02-01

    Combining the functional metabolic imaging and anatomical imaging, PET-CT stands for the highest level of current nuclear medical imaging techniques, and has been applying increasingly in acupuncture studies. However, owning to complexity of the brain function and sensitivity of brain metabolism, the lower reproducibility of cerebral function imaging even may reverse many results. This has been provoked more and more attention by researchers. Its main cause is intimately related to poor experimental methodology. For this reason, the present paper raises the quality control of the research on mechanisms of acupuncture in the process of application of PET-CT techniques from (1) the included standards of participants, (2) the preparation of participants during the scanning process of PET-CT, (3) the setting of the scanning parameters, (4) the used machine and the imaging reagent, (5) the analysis of dada, (6) the standardization of acupuncture manipulation, and (7) the designs of the acupuncture operation, needling opportunity and scanning opportunity, hoping to offer some beneficial information for the coming researches.

  7. Molecular PET/CT imaging-guided radiation therapy treatment planning.

    PubMed

    Zaidi, Habib; Vees, Hansjörg; Wissmeyer, Michael

    2009-09-01

    The role of positron emission tomography (PET) during the past decade has evolved rapidly from that of a pure research tool to a methodology of enormous clinical potential. (18)F-fluorodeoxyglucose (FDG)-PET is currently the most widely used probe in the diagnosis, staging, assessment of tumor response to treatment, and radiation therapy planning because metabolic changes generally precede the more conventionally measured parameter of change in tumor size. Data accumulated rapidly during the last decade, thus validating the efficacy of FDG imaging and many other tracers in a wide variety of malignant tumors with sensitivities and specificities often in the high 90 percentile range. As a result, PET/computed tomography (CT) had a significant impact on the management of patients because it obviated the need for further evaluation, guided further diagnostic procedures, and assisted in planning therapy for a considerable number of patients. On the other hand, the progress in radiation therapy technology has been enormous during the last two decades, now offering the possibility to plan highly conformal radiation dose distributions through the use of sophisticated beam targeting techniques such as intensity-modulated radiation therapy (IMRT) using tomotherapy, volumetric modulated arc therapy, and many other promising technologies for sculpted three-dimensional (3D) dose distribution. The foundation of molecular imaging-guided radiation therapy lies in the use of advanced imaging technology for improved definition of tumor target volumes, thus relating the absorbed dose information to image-based patient representations. This review documents technological advancements in the field concentrating on the conceptual role of molecular PET/CT imaging in radiation therapy treatment planning and related image processing issues with special emphasis on segmentation of medical images for the purpose of defining target volumes. There is still much more work to be done and many of

  8. Comparison of FDG-PET/CT images between chronic renal failure patients on hemodialysis and controls.

    PubMed

    Toriihara, Akira; Kitazume, Yoshio; Nishida, Hidenori; Kubota, Kazunori; Nakadate, Masashi; Tateishi, Ukihide

    2015-01-01

    The whole-body 2-deoxy-2-[(18)F]fluoro-D-glucose (FDG) distribution in chronic renal failure (CRF) patients on hemodialysis would be different from that in subjects with normal renal function, because they lack urinary FDG excretion and remain in a constant volume overload. We evaluated the difference in the physiological uptake pattern of FDG between chronic renal failure patients on hemodialysis and control subjects. The subjects for this retrospective study consisted of 24 chronic renal failure patients on hemodialysis (HD group) and 24 age- and sex-matched control subjects (NC group). Standardized uptake values normalized by the body weight (SUVbw), ideal body weight (SUVibw), lean body mass (SUVlbm), and body surface area (SUVbsa) in the cerebellum, lungs, liver, gluteal muscles and subcutaneous fat, spleen, thoracolumbar spine, thoracic and abdominal aorta, and right atrium were calculated in positron emission tomography/computed tomography (PET/CT) images. SUVbw in the gluteal muscles, subcutaneous fat, spleen and right atrium was significantly higher in the HD group as compared to that in the NC group (p < 0.05; unpaired t test). In addition, SUVibm, SUVlbm, as well as SUVbsa in the abdominal aorta were significantly higher in the HD group as compared to those in the NC group (p < 0.05; unpaired t test). In conclusion, as compared to normal subjects, chronic renal failure patients on hemodialysis show significantly higher physiological FDG uptake in the soft tissues, spleen and blood pool.

  9. Localized Prostate Cancer Detection with 18F FACBC PET/CT: Comparison with MR Imaging and Histopathologic Analysis

    PubMed Central

    Mena, Esther; Shih, Joanna; Pinto, Peter A.; Merino, Maria J.; Lindenberg, Maria L.; Bernardo, Marcelino; McKinney, Yolanda L.; Adler, Stephen; Owenius, Rikard; Choyke, Peter L.; Kurdziel, Karen A.

    2014-01-01

    Purpose To characterize uptake of 1-amino-3-fluorine 18-fluorocyclobutane-1-carboxylic acid (18F FACBC) in patients with localized prostate cancer, benign prostatic hyperplasia (BPH), and normal prostate tissue and to evaluate its potential utility in delineation of intraprostatic cancers in histopathologically confirmed localized prostate cancer in comparison with magnetic resonance (MR) imaging. Materials and Methods Institutional review board approval and written informed consent were obtained for this HIPAA-compliant prospective study. Twenty-one men underwent dynamic and static abdominopelvic 18F FACBC combined positron emission tomography (PET) and computed tomography (CT) and multiparametric (MP) 3-T endorectal MR imaging before robotic-assisted prostatectomy. PET/CT and MR images were coregistered by using pelvic bones as fiducial markers; this was followed by manual adjustments. Whole-mount histopathologic specimens were sliced with an MR-based patient-specific mold. 18F FACBC PET standardized uptake values (SUVs) were compared with those at MR imaging and histopathologic analysis for lesion- and sector-based (20 sectors per patient) analysis. Positive and negative predictive values for each modality were estimated by using generalized estimating equations with logit link function and working independence correlation structure. Results 18F FACBC tumor uptake was rapid but reversible. It peaked 3.6 minutes after injection and reached a relative plateau at 15–20 minutes (SUVmax[15–20min]). Mean prostate tumor SUVmax(15–20min) was significantly higher than that of the normal prostate (4.5 ± 0.5 vs 2.7 ± 0.5) (P < .001); however, it was not significantly different from that of BPH (4.3 ± 0.6) (P = .27). Sector-based comparison with histopathologic analysis, including all tumors, revealed sensitivity and specificity of 67% and 66%, respectively, for 18F FACBC PET/CT and 73% and 79%, respectively, for T2-weighted MR imaging. 18F FACBC PET/CT and MP MR

  10. Impact of metal artefacts due to EEG electrodes in brain PET/CT imaging

    NASA Astrophysics Data System (ADS)

    Lemmens, Catherine; Montandon, Marie-Louise; Nuyts, Johan; Ratib, Osman; Dupont, Patrick; Zaidi, Habib

    2008-08-01

    The goal of this study is to investigate the impact of electroencephalogram (EEG) electrodes on the visual quality and quantification of 18F-FDG PET images in neurological PET/CT examinations. For this purpose, the scans of 20 epilepsy patients with EEG monitoring were used. The CT data were reconstructed with filtered backprojection (FBP) and with a metal artefact reduction (MAR) algorithm. Both data sets were used for CT-based attenuation correction (AC) of the PET data. Also, a calculated AC (CALC) technique was considered. A volume of interest (VOI)-based analysis and a voxel-based quantitative analysis were performed to compare the different AC methods. Images were also evaluated visually by two observers. It was shown with simulations and phantom measurements that from the considered AC methods, the MAR-AC can be used as the reference in this setting. The visual assessment of PET images showed local hot spots outside the brain corresponding to the locations of the electrodes when using FBP-AC. In the brain, no abnormalities were observed. The quantitative analysis showed a very good correlation between PET-FBP-AC and PET-MAR-AC, with a statistically significant positive bias in the PET-FBP-AC images of about 5-7% in most brain voxels. There was also good correlation between PET-CALC-AC and PET-MAR-AC, but in the PET-CALC-AC images, regions with both a significant positive and negative bias were observed. EEG electrodes give rise to local hot spots outside the brain and a positive quantification bias in the brain. However, when diagnosis is made by mere visual assessment, the presence of EEG electrodes does not seem to alter the diagnosis. When quantification is performed, the bias becomes an issue especially when comparing brain images with and without EEG monitoring.

  11. 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

  12. Quantitative imaging of (124)I with PET/ CT in pretherapy lesion dosimetry. Effects impairing image quantification and their corrections.

    PubMed

    Jentzen, W; Freudenberg, L; Bockisch, A

    2011-02-01

    Iodine-131-labelled agents are successfully used in cancer treatment. In the pretherapy dosimetry approach, positron emission tomography/computed tomography (PET/CT) using (124)I provides a modality to estimate absorbed dose to tumours and can be considered as the preferred imaging method for this purpose in (131)I radiopharmaceutical therapies. For accurate dosimetry, serial measurements of activity concentrations (ACs) over an appropriate time period are necessary. Consequently, accurate AC determination is of paramount importance in PET/CT-based lesion dosimetry using (124)I-labelled agents. After presenting an historical overview of (124)I clinical application, this review focuses on factors impairing PET image quantification accuracy and on methods of correcting for these effects. Specifically, the emission of prompt gamma photons in the (124)I decay process that are detected in coincidence with each other and with the annihilation photon, and the low (124)I positron branching ration of only 23% raise concerns regarding image quantification accuracy. This review discusses this prompt gamma effect, its impact and approaches to correct for this phenomenon. In (124)I lesion dosimetry, recovery coefficients (RCs) are commonly used to compensate primarily for partial-volume effect but also, in a simplistic way, for prompt gamma coincidence effect; the main methodological factors affecting the RC-corrected (124)I AC are described. Finally, special issues in image (124)I quantification are reviewed, including coadministration of high therapeutic activities of 131I, shine-through artefact, and transmission-contamination effect occurring in stand-alone PET systems.

  13. Uterine leiomyosarcoma metastatic to thyroid shown by (18)F-FDG PET/CT imaging.

    PubMed

    Gauthé, M; Testart Dardel, N; Nascimento, C; Trassard, M; Banal, A; Alberini, J-L

    About one third of focal thyroid uptakes in a fluorodeoxyglucose (FDG) positron emission tomography/computerized tomography (PET/CT) study are malignant, the most frequent histological type being papillary carcinoma. Metastases to the thyroid account for approximately 7.5% of thyroid malignancies and come mainly from kidney, lung, head and neck, and breast cancers. We report the case of a 64-year-old woman presenting a fast growing thyroid nodule whose primitive or metastatic origin was not obvious, for which (18)F-FDG PET/CT helped in the diagnostic process and in the later management of the patient. Histopathologic findings finally revealed a metastasis of uterine leiomyosarcoma.

  14. SU-E-J-275: Review - Computerized PET/CT Image Analysis in the Evaluation of Tumor Response to Therapy

    SciTech Connect

    Lu, W; Wang, J; Zhang, H

    2015-06-15

    Purpose: To review the literature in using computerized PET/CT image analysis for the evaluation of tumor response to therapy. Methods: We reviewed and summarized more than 100 papers that used computerized image analysis techniques for the evaluation of tumor response with PET/CT. This review mainly covered four aspects: image registration, tumor segmentation, image feature extraction, and response evaluation. Results: Although rigid image registration is straightforward, it has been shown to achieve good alignment between baseline and evaluation scans. Deformable image registration has been shown to improve the alignment when complex deformable distortions occur due to tumor shrinkage, weight loss or gain, and motion. Many semi-automatic tumor segmentation methods have been developed on PET. A comparative study revealed benefits of high levels of user interaction with simultaneous visualization of CT images and PET gradients. On CT, semi-automatic methods have been developed for only tumors that show marked difference in CT attenuation between the tumor and the surrounding normal tissues. Quite a few multi-modality segmentation methods have been shown to improve accuracy compared to single-modality algorithms. Advanced PET image features considering spatial information, such as tumor volume, tumor shape, total glycolytic volume, histogram distance, and texture features have been found more informative than the traditional SUVmax for the prediction of tumor response. Advanced CT features, including volumetric, attenuation, morphologic, structure, and texture descriptors, have also been found advantage over the traditional RECIST and WHO criteria in certain tumor types. Predictive models based on machine learning technique have been constructed for correlating selected image features to response. These models showed improved performance compared to current methods using cutoff value of a single measurement for tumor response. Conclusion: This review showed that

  15. Renal Cell Carcinoma with Paraneoplastic Manifestations: Imaging with CT and F-18 FDG PET/CT.

    PubMed

    Nguyen, Ba D; Roarke, Michael C

    2007-01-01

    We present a case of renal cell carcinoma with prominent inflammatory and paraneoplastic manifestations. The initial CT detection of renal malignancy and subsequent post-therapeutic F-18 FDG PET/CT diagnosis of occult osseous metastasis were based on the patient's anemia, thrombocytosis and abnormally increased levels of serum C-reactive protein.

  16. 11C-Acetate PET/CT Imaging in Localized Prostate Cancer: A study with MRI and Histopathologic Correlation

    PubMed Central

    Mena, Esther; Turkbey, Baris; Mani, Haresh; Adler, Stephen; Valera, Vladimir A.; Bernardo, Marcelino; Shah, Vijay; Pohida, Thomas; McKinney, Yolanda; Kwarteng, Gideon; Daar, Dagane; Lindenberg, Maria L.; Eclarinal, Philip; Wade, Revia; Linehan, W. Marston; Merino, Maria J.; Pinto, Peter A.; Choyke, Peter L.; Kurdziel, Karen A.

    2012-01-01

    This work characterizes the uptake of 11C-Acetate in prostate cancer (PCa), benign prostate hyperplasia (BPH) and normal prostate tissue in comparison with multi-parametric MRI, whole mount histopathology and clinical markers, to evaluate its potential utility for delineating intra-prostatic tumors in a population of patients with localized PCa. METHODS 39 men with presumed localized PCa underwent dynamic/static abdomen-pelvic 11C-Acetate PET/CT for 30-minutes and 3T multi-parametric (MP) MRI prior to prostatectomy. PET/CT images were registered to MRI using pelvic bones for initial rotation-translation, followed by manual adjustments to account for prostate motion and deformation from the MRI endorectal coil. Whole-mount pathology specimens were sectioned using an MRI-based patient specific mold resulting in improved registration between the MRI, PET and pathology. 11C-Acetate PET standardized uptake values were compared with MP-MRI and pathology. RESULTS 11C-Acetate uptake was rapid but reversible, peaking at 3–5 minutes post-injection and reaching a relative plateau at ~10 minutes. The average SUVmax(10–12min) of tumors was significantly higher than that of normal prostate tissue (4.4±2.05, range 1.8–9.2 vs. 2.1±0.94, range 0.7–3.4; p<0.001); however it was not significantly different from benign prostatic hyperplasia (4.8±2.01; range 1.8–8.8). A sector-based comparison with histopathology, including all tumors > 0.5 cm, revealed a sensitivity and specificity of 61.6 % and 80.0 % for 11C-Acetate PET/CT, and 82.3% and 95.1% for MRI, respectively. Considering only tumors >0.9 cm the 11C-Acetate accuracy was comparable to that of MRI. In a small cohort (n=9), 11C-Acetate uptake was independent of fatty acid synthase expression based on immunohistochemistry. CONCLUSION 11C-Acetate PET/CT demonstrates higher uptake in tumor foci than normal prostate tissue; however 11C-Acetate uptake in tumors is similar to BPH nodules. While 11C-Acetate PET/CT is not

  17. Transconvolution and the virtual positron emission tomograph-A new method for cross calibration in quantitative PET/CT imaging

    SciTech Connect

    Prenosil, George A.; Weitzel, Thilo; Hentschel, Michael; Klaeser, Bernd; Krause, Thomas

    2013-06-15

    Purpose: Positron emission tomography (PET)/computed tomography (CT) measurements on small lesions are impaired by the partial volume effect, which is intrinsically tied to the point spread function of the actual imaging system, including the reconstruction algorithms. The variability resulting from different point spread functions hinders the assessment of quantitative measurements in clinical routine and especially degrades comparability within multicenter trials. To improve quantitative comparability there is a need for methods to match different PET/CT systems through elimination of this systemic variability. Consequently, a new method was developed and tested that transforms the image of an object as produced by one tomograph to another image of the same object as it would have been seen by a different tomograph. The proposed new method, termed Transconvolution, compensates for differing imaging properties of different tomographs and particularly aims at quantitative comparability of PET/CT in the context of multicenter trials. Methods: To solve the problem of image normalization, the theory of Transconvolution was mathematically established together with new methods to handle point spread functions of different PET/CT systems. Knowing the point spread functions of two different imaging systems allows determining a Transconvolution function to convert one image into the other. This function is calculated by convolving one point spread function with the inverse of the other point spread function which, when adhering to certain boundary conditions such as the use of linear acquisition and image reconstruction methods, is a numerically accessible operation. For reliable measurement of such point spread functions characterizing different PET/CT systems, a dedicated solid-state phantom incorporating {sup 68}Ge/{sup 68}Ga filled spheres was developed. To iteratively determine and represent such point spread functions, exponential density functions in combination

  18. PET/CT and Bremsstrahlung Imaging After 90Y DOTANOC Therapy for Rectal Net With Liver Metastases.

    PubMed

    Abdülrezzak, Ümmühan; Kula, Mustafa; Tutuş, Ahmet; Buyukkaya, Fikret; Karaca, Halit

    2015-10-01

    Peptide receptor radionuclide therapy with Lu or Y is promising with successful results in somatostatin receptor-positive tumors. In all radiation therapies, knowledge of the radiation dose received by the target, and other organs in the body is essential to evaluate the risks and benefits of any procedure. We report a case of liver metastases from a rectal neuroendocrine tumor, which was treated with Y DOTANOC. Posttreatment whole-body planar images were acquired through Bremsstrahlung radiations of Y on a γ-camera, and thoracolumbar PET/CT images were acquired on PET.

  19. PET/CT imaging: The incremental value of assessing the glucose metabolic phenotype and the structure of cancers in a single examination.

    PubMed

    Czernin, Johannes; Benz, Matthias R; Allen-Auerbach, Martin S

    2010-03-01

    PET/CT with the glucose analogue FDG is emerging as the most important diagnostic imaging tool in oncology. More than 2000 PET/CT scanners are operational worldwide and its unique role for diagnosing, staging, restaging and therapeutic monitoring in cancer is undisputed. Studies conducted in thousands of cancer patients have clearly indicated that the combination of molecular PET with anatomical CT imaging provides incremental diagnostic value over PET or CT alone. State of the art imaging protocols combine fully diagnostic CT scans with quality whole body PET surveys. The current review briefly describes the biological alterations of cancer cells that result in their switch to a strongly glycolytic phenotype. Different whole body imaging protocols are discussed. We summarize the evidence for the incremental value of PET/CT over CT and PET alone using imaging of sarcoma as an example. Following this section we discuss the performance of FDG-PET/CT imaging for staging, restaging and monitoring of head and neck cancer, solitary lung nodules and lung cancer, breast cancer, colorectal cancer, lymphoma and unknown primary tumors. Finally, the recently emerging evidence of a substantial impact of PET/CT imaging on patient management is presented.

  20. Can technical characteristics predict clinical performance in PET/CT imaging? A correlation study for thyroid cancer diagnosis

    NASA Astrophysics Data System (ADS)

    Kallergi, Maria; Menychtas, Dimitrios; Georgakopoulos, Alexandros; Pianou, Nikoletta; Metaxas, Marinos; Chatziioannou, Sofia

    2013-03-01

    The purpose of this study was to determine whether image characteristics could be used to predict the outcome of ROC studies in PET/CT imaging. Patients suspected for recurrent thyroid cancer underwent a standard whole body (WB) examination and an additional high-resolution head-and-neck (HN) F18-FDG PET/CT scan. The value of the latter was determined with an ROC study, the results of which showed that the WB+HN combination was better than WB alone for thyroid cancer detection and diagnosis. Following the ROC experiment, the WB and HN images of confirmed benign or malignant thyroid disease were analyzed and first and second order textural features were determined. Features included minimum, mean, and maximum intensity, as well as contrast in regions of interest encircling the thyroid lesions. Lesion size and standard uptake values (SUV) were also determined. Bivariate analysis was applied to determine relationships between WB and HN features and between observer ROC responses and the various feature values. The two sets showed significant associations in the values of SUV, contrast, and lesion size. They were completely different when the intensities were considered; no relationship was found between the WB minimum, maximum, and mean ROI values and their HN counterparts. SUV and contrast were the strongest predictors of ROC performance on PET/CT examinations of thyroid cancer. The high resolution HN images seem to enhance these relationships but without a single dramatic effect as was projected from the ROC results. A combination of features from both WB and HN datasets may possibly be a more robust predictor of ROC performance.

  1. Inter- and Intra- observer agreement of FDG-PET/CT image interpretation in patients referred for assessment of Cardiac Sarcoidosis.

    PubMed

    Ohira, Hiroshi; Mc Ardle, Brian; deKemp, Robert A; Nery, Pablo B; Juneau, Daniel; Renaud, Jennifer M; Klein, Ran; Clarkin, Owen; MacDonald, Karen; Leung, Eugene; Nair, Girish; Beanlands, Rob S B; Birnie, David

    2017-03-02

    Recent studies have reported the usefulness of (18)F-fluoro-2-deoxyglucose positron emission tomography (FDG-PET) in aiding with the diagnosis and management of patients with cardiac sarcoidosis (CS). However, the image interpretation of FDG-PET for CS is sometimes challenging. We sought to investigate the inter- and intra-observer agreement and explore factors which lead to important discrepancies between readers. METHODS: We studied consecutive patients with no significant coronary artery disease who were referred for assessment of CS. Two experienced readers blinded to clinical information, imaging reports, independently reviewed FDG-PET/CT images. FDG-PET/CT images were interpreted according to a predefined standard operating procedure, with cardiac FDG uptake patterns categorized into 5 patterns; 1) none, 2) focal, 3) focal on diffuse, 4) diffuse and 5) isolated lateral wall and/or basal uptake. Overall image assessment was classified as either consistent with active CS or not. RESULTS: One hundred scans were included from 71 patients. Of these, 46 underwent FDG-PET/CT with no-restricted diet (no-restriction group) and 54 underwent FDG-PET/CT with low-carbohydrate, high fat and protein-permitted diet (low-carb group). There was agreement of the interpretation category in 74 of 100 scans. Kappa value of agreement among all 5 categories was 0.64 indicating moderate agreement. For overall clinical interpretation, there was agreement in 93 of 100 scans (kappa = 0.85). When scans were divided into the preparation groups; there was trend towards higher agreement in the low-carb group vs no-restriction (80% vs 67%, P = 0.08). Regarding the overall clinical interpretation, there was also trend towards greater agreement in the low-carb group vs no-restriction (96% vs 89%, P = 0.08). CONCLUSION: The inter-observer agreement of cardiac FDG uptake image patterns was moderate. However, agreement was better regarding overall interpretation of CS. Detailed pre-scan dietary

  2. Ambient radiation levels in positron emission tomography/computed tomography (PET/CT) imaging center

    PubMed Central

    Santana, Priscila do Carmo; de Oliveira, Paulo Marcio Campos; Mamede, Marcelo; Silveira, Mariana de Castro; Aguiar, Polyanna; Real, Raphaela Vila; da Silva, Teógenes Augusto

    2015-01-01

    Objective To evaluate the level of ambient radiation in a PET/CT center. Materials and Methods Previously selected and calibrated TLD-100H thermoluminescent dosimeters were utilized to measure room radiation levels. During 32 days, the detectors were placed in several strategically selected points inside the PET/CT center and in adjacent buildings. After the exposure period the dosimeters were collected and processed to determine the radiation level. Results In none of the points selected for measurements the values exceeded the radiation dose threshold for controlled area (5 mSv/year) or free area (0.5 mSv/year) as recommended by the Brazilian regulations. Conclusion In the present study the authors demonstrated that the whole shielding system is appropriate and, consequently, the workers are exposed to doses below the threshold established by Brazilian standards, provided the radiation protection standards are followed. PMID:25798004

  3. PET/CT imaging for treatment verification after proton therapy: A study with plastic phantoms and metallic implants

    SciTech Connect

    Parodi, Katia; Paganetti, Harald; Cascio, Ethan; Flanz, Jacob B.; Bonab, Ali A.; Alpert, Nathaniel M.; Lohmann, Kevin; Bortfeld, Thomas

    2007-02-15

    The feasibility of off-line positron emission tomography/computed tomography (PET/CT) for routine three dimensional in-vivo treatment verification of proton radiation therapy is currently under investigation at Massachusetts General Hospital in Boston. In preparation for clinical trials, phantom experiments were carried out to investigate the sensitivity and accuracy of the method depending on irradiation and imaging parameters. Furthermore, they addressed the feasibility of PET/CT as a robust verification tool in the presence of metallic implants. These produce x-ray CT artifacts and fluence perturbations which may compromise the accuracy of treatment planning algorithms. Spread-out Bragg peak proton fields were delivered to different phantoms consisting of polymethylmethacrylate (PMMA), PMMA stacked with lung and bone equivalent materials, and PMMA with titanium rods to mimic implants in patients. PET data were acquired in list mode starting within 20 min after irradiation at a commercial luthetium-oxyorthosilicate (LSO)-based PET/CT scanner. The amount and spatial distribution of the measured activity could be well reproduced by calculations based on the GEANT4 and FLUKA Monte Carlo codes. This phantom study supports the potential of millimeter accuracy for range monitoring and lateral field position verification even after low therapeutic dose exposures of 2 Gy, despite the delay between irradiation and imaging. It also indicates the value of PET for treatment verification in the presence of metallic implants, demonstrating a higher sensitivity to fluence perturbations in comparison to a commercial analytical treatment planning system. Finally, it addresses the suitability of LSO-based PET detectors for hadron therapy monitoring. This unconventional application of PET involves countrates which are orders of magnitude lower than in diagnostic tracer imaging, i.e., the signal of interest is comparable to the noise originating from the intrinsic radioactivity of

  4. WE-AB-204-01: Performance Characterization of Regularized-Reconstruction Algorithm for 90Y PET/CT Images

    SciTech Connect

    Siman, W; Kappadath, S; Mawlawi, O

    2015-06-15

    Purpose: {sup 90}Y PET/CT imaging and quantification have recently been suggested as an approach of treatment verification. However, due to low positron yield (32ppm), the {sup 90}Y-PET/CT images are very noisy. Iterative reconstruction techniques that employ regularization, e.g. block sequential regularized expectation maximization (BSREM) algorithm (recently implemented on GE scanners – QClear™), has the potential to increase quantitative accuracy with lower noise penalty compared to OSEM. Our aim is to investigate the performance of RR algorithms in {sup 90}Y PET/CT studies. Methods: A NEMA IEC phantom filled with 3GBq {sup 90}YCl{sub 2} (to simulate patient treatment) was imaged on GE-D690 for 1800s/bed. The sphere-to-background ratio of 7. The data were reconstructed using OSEM and BSREM with PSF modeling and TOF correction while varying the iterations (IT) from 1–6 with fixed 24subsets. For BSREM, the edge-preservation parameter (γ ) was 2 and the penalty-parameters (β) was varied 350–950. In all cases a post-reconstruction filter of 5.2mm (2pixel) transaxial and standard z-axis were used. Sphere average activity concentration (AC) and background standard deviation (SD) were then calculated from VOIs drawn in the spheres and background. Results: Increasing IT from 1to6, the %SD in OSEM increased from 30% to 80%, whereas %SD in BSREM images increased by <5% for all βs. BSREM with β=350 didn’t offer any improvement over OSEM (convergence of mean achieved at 2 IT, in this study). Increasing β from 350 to 950 reduced the AC accuracy of small spheres (<20mm) by 10% and noise from 40% to 20%, which resulted in CNR increase from 11 to 17. Conclusion: In count-limited studies such as {sup 90}Y PET/CT, BSREM can be used to suppress image noise and increase CNR at the expense of a relatively small decrease of quantitative accuracy. The BSREM parameters need to be optimized for each study depending on the radionuclides and count densities. Research

  5. High-throughput multiple-mouse imaging with micro-PET/CT for whole-skeleton assessment.

    PubMed

    Yagi, Masashi; Arentsen, Luke; Shanley, Ryan M; Hui, Susanta K

    2014-11-01

    Recent studies have proven that skeleton-wide functional assessment is essential to comprehensively understand physiological aspects of the skeletal system. Therefore, in contrast to regional imaging studies utilizing a multiple-animal holder (mouse hotel), we attempted to develop and characterize a multiple-mouse imaging system with micro-PET/CT for high-throughput whole-skeleton assessment. Using items found in a laboratory, a simple mouse hotel that houses four mice linked with gas anesthesia was constructed. A mouse-simulating phantom was used to measure uniformity in a cross sectional area and flatness (Amax/Amin*100) along the axial, radial and tangential directions, where Amax and Amin are maximum and minimum activity concentration in the profile, respectively. Fourteen mice were used for single- or multiple-micro-PET/CT scans. NaF uptake was measured at eight skeletal sites (skull to tibia). Skeletal (18)F activities measured with mice in the mouse hotel were within 1.6 ± 4% (mean ± standard deviation) of those measured with mice in the single-mouse holder. Single-holder scanning yields slightly better uniformity and flatness over the hotel. Compared to use of the single-mouse holder, scanning with the mouse hotel reduced study time (by 65%), decreased the number of scans (four-fold), reduced cost, required less computer storage space (40%), and maximized (18)F usage. The mouse hotel allows high-throughput, quantitatively equivalent scanning compared to the single-mouse holder for micro-PET/CT imaging for whole-skeleton assessment of mice.

  6. Design and performance of a respiratory amplitude gating device for PET/CT imaging

    SciTech Connect

    Chang Guoping; Chang Tingting; Clark, John W. Jr.; Mawlawi, Osama R.

    2010-04-15

    Purpose: Recently, the authors proposed a free-breathing amplitude gating (FBAG) technique for PET/CT scanners. The implementation of this technique required specialized hardware and software components that were specifically designed to interface with commercial respiratory gating devices to generate the necessary triggers required for the FBAG technique. The objective of this technical note is to introduce an in-house device that integrates all the necessary hardware and software components as well as tracks the patient's respiratory motion to realize amplitude gating on PET/CT scanners. Methods: The in-house device is composed of a piezoelectric transducer coupled to a data-acquisition system in order to monitor the respiratory waveform. A LABVIEW program was designed to control the data-acquisition device and inject triggers into the PET list stream whenever the detected respiratory amplitude crossed a predetermined amplitude range. A timer was also programmed to stop the scan when the accumulated time within the selected amplitude range reached a user-set interval. This device was tested using a volunteer and a phantom study. Results: The results from the volunteer and phantom studies showed that the in-house device can detect similar respiratory signals as commercially available respiratory gating systems and is able to generate the necessary triggers to suppress respiratory motion artifacts. Conclusions: The proposed in-house device can be used to implement the FBAG technique in current PET/CT scanners.

  7. [{sup 18}F]Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (PET/CT) Physiologic Imaging of Choroidal Melanoma: Before and After Ophthalmic Plaque Radiation Therapy

    SciTech Connect

    Finger, Paul T.; Chin, Kimberly J.

    2011-01-01

    Purpose: To evaluate changes in [{sup 18}F]fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) standardized uptake values (SUV) in uveal melanoma before and after plaque brachytherapy. Methods and Materials: A cohort of 217 patients diagnosed with uveal melanoma and eligible for ophthalmic plaque brachytherapy underwent preoperative PET/CT to evaluate their intraocular tumor and screen for metastasis. Subsequent to undergoing plaque brachytherapy, patients' PET/CT SUV were periodically reevaluated over 42 months. Results: In this series, 37 (17%) choroidal melanoma patients were found to have an SUV of >2.0. Of these, 18 patients were able to undergo interval follow-up PET/CT scanning. There were 3 patients with T2, 11 patients with T3, and 4 patients with T4 melanomas according to 7th edition AJCC-UICC criteria. Mean apical thickness was 8.8 mm (range, 3-12.3 mm), and the largest mean tumor diameter was 15.1 mm (range, 12-19.9 mm). The mean initial SUV was 3.7 (range, 2.1-7.3). Patients were followed for a median 16 months (range, 6-42 months). The median time to a tumor SUV of 0 was 8.0 months (range, 6-18 months). There was one case of one interval increase in SUV that diminished after circumferential laser treatment. Conclusions: Intraocular PET/CT imaging provides a physiological assessment of tumor metabolism that can be used to evaluate changes after treatment. In this study, ophthalmic plaque radiation therapy was associated with extinguished tumor PET/CT SUV over time. PET/CT imaging can be used to assess choroidal melanomas for their response to treatment.

  8. Evaluation of 18F-FDG PET/CT as a diagnostic imaging and staging tool for feline oral squamous cell carcinoma.

    PubMed

    Randall, E K; Kraft, S L; Yoshikawa, H; LaRue, S M

    2016-03-01

    18F-fluorodeoxyglucose positron emission tomography combined with computed tomography (18FDG-PET/CT) has been shown to be effective for staging human oral squamous cell carcinoma (SCC) but its application for cats with oral SCC is unknown. Twelve cats with biopsy-proven oral SCC were imaged with whole body 18FDG-PET/CT to determine its value as a diagnostic imaging and staging tool and fine needle aspirates were obtained of accessible regional lymph nodes. All tumors were FDG avid and conspicuous on 18FDG-PET/CT images, with an average of the maximum standardized uptake value 9.88 ± 5.33 SD (range 2.9-24.9). Soft tissue infiltrative tumors that were subtle and ill defined on CT were highly visible and more extensive on FDG-PET/CT. Tumors invading the osseous structures were more similar in extent on 18FDG-PET/CT and CT although they were more conspicuous on PET images. Three cytologically confirmed metastases were hypermetabolic on PET, while two of those metastases were equivocal on CT.

  9. PET/CT imaging of age- and task-associated differences in muscle activity during fatiguing contractions

    PubMed Central

    Kalliokoski, Kari K.; Block, Derek E.; Gould, Jeffrey R.; Klingensmith, William C.; Enoka, Roger M.

    2013-01-01

    The study compared positron emission tomography/computed tomography (PET/CT) of [18F]-2-fluoro-2-deoxy-d-glucose ([18F]-FDG) uptake by skeletal muscles and the amount of muscle activity as indicated by surface electromyographic (EMG) recordings when young and old men performed fatiguing isometric contractions that required either force or position control. EMG signals were recorded from thigh muscles of six young men (26 ± 6 yr) and six old men (77 ± 6 yr) during fatiguing contractions with the knee extensors. PET/CT scans were performed immediately after task failure. Glucose uptake in 24 leg muscles, quantified as standardized uptake values, was greater for the old men after the force task and differed across tasks for the young men (force, 0.64 ± 0.3 g/ml; position, 0.73 ± 0.3 g/ml), but not the old men (force, 0.84 ± 0.3 g/ml; position, 0.79 ± 0.26 g/ml) (age × task interaction; P < 0.001). In contrast, the rate of increase in EMG amplitude for the agonist muscles was greater for the young men during the two contractions and there was no difference for either group of subjects in the rate of increase in EMG amplitude across the two tasks. The imaging estimates of glucose uptake indicated age- and task-dependent differences in the spatial distribution of [18F]-FDG uptake by skeletal muscles during fatiguing contractions. The findings demonstrate that PET/CT imaging of [18F]-FDG uptake, but not surface EMG recordings, detected the modulation of muscle activity across the fatiguing tasks by the young men but not the old men. PMID:23412899

  10. Contribution of nonattenuation-corrected images on FDG-PET/CT in the assessment of solitary pulmonary nodules.

    PubMed

    Şahin, Ertan; Kara, Ahmet; Elboğa, Umut

    2016-12-01

    In this study, we aim to determine the diagnostic performance of nonattenuation-corrected (NAC) and attenuation-corrected (AC) FDG-PET/CT images in the assessment of solitary pulmonary nodule (SPN). We reviewed the images of 41 patients who underwent FDG-PET/CT to diagnose SPNs. The visual analysis of FDG uptake intensity in SPN on AC and NAC PET images was made using a four-point score from 1 to 4 on both AC and NAC PET images. The cutoff value of SUVmax and visual uptake scores for malignancy were defined as ≥2.5 and ≥3, respectively. The significant visual uptake (≥2 visual point score) on AC and NAC PET images was considered to be positive 18F-FDG PET findings for lesion detectability. The sensitivity, specificity and diagnostic accuracy were calculated for AC and NAC PET images. Based on the histopathology and imaging data, 22 of the SPNs (54 %) were malignant and 19 of them (46 %) were benign. The sensitivity and NPV were found to be 100 % in the detection of SPNs for AC and NAC PET images. For all SPNs and SPNs ≤2 cm, NAC PET image had a higher diagnostic performance for the SPN characterization as malignant or benign, when compared with AC PET image. The success rates of AC and NAC PET images were found to be similar for the detection of SPNs. NAC PET image had a higher diagnostic performance for the SPN characterization. It is thought that NAC PET image may provide additional contributions for characterization of SPNs.

  11. PET/CT imaging of neuroendocrine tumors with 68Gallium-labeled somatostatin analogues: An overview and single institutional experience from India

    PubMed Central

    Sharma, Punit; Singh, Harmandeep; Bal, Chandrasekhar; Kumar, Rakesh

    2014-01-01

    Neuroendocrine tumors (NETs) are rare neoplasms characterized by overexpression of somatostatin receptors (SSTRs). Functional imaging plays a crucial role in management of NETs. Recently, positron emission tomography/computed tomography (PET/CT) with 68Gallium (68Ga)-labeled somatostatin analogues has shown excellent results for imaging of NETs and better results than conventional SSTR scintigraphy. In this review we have discussed the utility of 68Ga-labeled somatostatin analogue PET/CT in NETs for various established and potential indications. In addition we have also shared our own experience from a tertiary care center in India. PMID:24591775

  12. Early Detection of Bone Metastasis in Small Cell Neuroendocrine Carcinoma of the Cervix by 68Ga-DOTATATE PET/CT Imaging.

    PubMed

    Damian, Andres; Lago, Graciela; Rossi, Susana; Alonso, Omar; Engler, Henry

    2017-03-01

    The neuroendocrine small cell carcinoma of the cervix is a rare malignancy that has a poor prognosis due to early lymphatic and hematogenous spread. We herein report a case of a 27- year-old woman who was referred for initial staging of a neuroendocrine small cell carcinoma with previous unremarkable structural imaging. Ga-DOTATATE PET/CT revealed focal uptake at the primary tumor and in a solitary pelvic bone lesion suggestive of metastases that was further confirmed by CT-guided biopsy. Somatostatin receptor PET/CT may be a useful image modality for early detection of metastases to guide treatment in these patients.

  13. Imaging and dosimetric errors in 4D PET/CT-guided radiotherapy from patient-specific respiratory patterns: a dynamic motion phantom end-to-end study

    NASA Astrophysics Data System (ADS)

    Bowen, S. R.; Nyflot, M. J.; Herrmann, C.; Groh, C. M.; Meyer, J.; Wollenweber, S. D.; Stearns, C. W.; Kinahan, P. E.; Sandison, G. A.

    2015-05-01

    Effective positron emission tomography / computed tomography (PET/CT) guidance in radiotherapy of lung cancer requires estimation and mitigation of errors due to respiratory motion. An end-to-end workflow was developed to measure patient-specific motion-induced uncertainties in imaging, treatment planning, and radiation delivery with respiratory motion phantoms and dosimeters. A custom torso phantom with inserts mimicking normal lung tissue and lung lesion was filled with [18F]FDG. The lung lesion insert was driven by six different patient-specific respiratory patterns or kept stationary. PET/CT images were acquired under motionless ground truth, tidal breathing motion-averaged (3D), and respiratory phase-correlated (4D) conditions. Target volumes were estimated by standardized uptake value (SUV) thresholds that accurately defined the ground-truth lesion volume. Non-uniform dose-painting plans using volumetrically modulated arc therapy were optimized for fixed normal lung and spinal cord objectives and variable PET-based target objectives. Resulting plans were delivered to a cylindrical diode array at rest, in motion on a platform driven by the same respiratory patterns (3D), or motion-compensated by a robotic couch with an infrared camera tracking system (4D). Errors were estimated relative to the static ground truth condition for mean target-to-background (T/Bmean) ratios, target volumes, planned equivalent uniform target doses, and 2%-2 mm gamma delivery passing rates. Relative to motionless ground truth conditions, PET/CT imaging errors were on the order of 10-20%, treatment planning errors were 5-10%, and treatment delivery errors were 5-30% without motion compensation. Errors from residual motion following compensation methods were reduced to 5-10% in PET/CT imaging, <5% in treatment planning, and <2% in treatment delivery. We have demonstrated that estimation of respiratory motion uncertainty and its propagation from PET/CT imaging to RT planning, and RT

  14. Impact of CT attenuation correction method on quantitative respiratory-correlated (4D) PET/CT imaging

    SciTech Connect

    Nyflot, Matthew J.; Lee, Tzu-Cheng; Alessio, Adam M.; Kinahan, Paul E.; Wollenweber, Scott D.; Stearns, Charles W.; Bowen, Stephen R.

    2015-01-15

    Purpose: Respiratory-correlated positron emission tomography (PET/CT) 4D PET/CT is used to mitigate errors from respiratory motion; however, the optimal CT attenuation correction (CTAC) method for 4D PET/CT is unknown. The authors performed a phantom study to evaluate the quantitative performance of CTAC methods for 4D PET/CT in the ground truth setting. Methods: A programmable respiratory motion phantom with a custom movable insert designed to emulate a lung lesion and lung tissue was used for this study. The insert was driven by one of five waveforms: two sinusoidal waveforms or three patient-specific respiratory waveforms. 3DPET and 4DPET images of the phantom under motion were acquired and reconstructed with six CTAC methods: helical breath-hold (3DHEL), helical free-breathing (3DMOT), 4D phase-averaged (4DAVG), 4D maximum intensity projection (4DMIP), 4D phase-matched (4DMATCH), and 4D end-exhale (4DEXH) CTAC. Recovery of SUV{sub max}, SUV{sub mean}, SUV{sub peak}, and segmented tumor volume was evaluated as RC{sub max}, RC{sub mean}, RC{sub peak}, and RC{sub vol}, representing percent difference relative to the static ground truth case. Paired Wilcoxon tests and Kruskal–Wallis ANOVA were used to test for significant differences. Results: For 4DPET imaging, the maximum intensity projection CTAC produced significantly more accurate recovery coefficients than all other CTAC methods (p < 0.0001 over all metrics). Over all motion waveforms, ratios of 4DMIP CTAC recovery were 0.2 ± 5.4, −1.8 ± 6.5, −3.2 ± 5.0, and 3.0 ± 5.9 for RC{sub max}, RC{sub peak}, RC{sub mean}, and RC{sub vol}. In comparison, recovery coefficients for phase-matched CTAC were −8.4 ± 5.3, −10.5 ± 6.2, −7.6 ± 5.0, and −13.0 ± 7.7 for RC{sub max}, RC{sub peak}, RC{sub mean}, and RC{sub vol}. When testing differences between phases over all CTAC methods and waveforms, end-exhale phases were significantly more accurate (p = 0.005). However, these differences were driven by

  15. Morphology supporting function: attenuation correction for SPECT/CT, PET/CT, and PET/MR imaging

    PubMed Central

    Lee, Tzu C.; Alessio, Adam M.; Miyaoka, Robert M.; Kinahan, Paul E.

    2017-01-01

    Both SPECT, and in particular PET, are unique in medical imaging for their high sensitivity and direct link to a physical quantity, i.e. radiotracer concentration. This gives PET and SPECT imaging unique capabilities for accurately monitoring disease activity for the purposes of clinical management or therapy development. However, to achieve a direct quantitative connection between the underlying radiotracer concentration and the reconstructed image values several confounding physical effects have to be estimated, notably photon attenuation and scatter. With the advent of dual-modality SPECT/CT, PET/CT, and PET/MR scanners, the complementary CT or MR image data can enable these corrections, although there are unique challenges for each combination. This review covers the basic physics underlying photon attenuation and scatter and summarizes technical considerations for multimodal imaging with regard to PET and SPECT quantification and methods to address the challenges for each multimodal combination. PMID:26576737

  16. A Comparative Study of Noninvasive Hypoxia Imaging with 18F-Fluoroerythronitroimidazole and 18F-Fluoromisonidazole PET/CT in Patients with Lung Cancer

    PubMed Central

    Huang, Yong; Yu, Qingxi; Zhu, Shouhui; Wang, Suzhen; Zhao, Shuqiang; Hu, Xudong; Yu, Jinming; Yuan, Shuanghu

    2016-01-01

    Purpose This is a clinical study to compare noninvasive hypoxia imaging using 18F-fluoroerythronitroimidazole (18F-FETNIM) and 18F-fluoromisonidazole (18F-FMISO) positron emission tomography/computed tomography (PET/CT) in patients with inoperable stages III–IV lung cancer. Methods A total of forty-two patients with inoperable stages III–IV lung cancer underwent 18F-FETNIM PET/CT (n = 18) and 18F-FMISO PET/CT (n = 24) before chemo/radiation therapy. The standard uptake values (SUVs) of malignant and normal tissues depict 18F-FETNIM PET/CT and 18F-FMISO PET/CT uptake. Tumor-to-blood ratios (T/B) were used to quantify hypoxia. Results All patients with lung cancer underwent 18F-FETNIM PET/CT and 18F-FMISO PET/CT successfully. Compared to 18F-FMISO, 18F-FETNIM showed similar uptake in muscle, thyroid, spleen, pancreas, heart, lung and different uptake in blood, liver, and kidney. Significantly higher SUV and T/B ratio with 18F-FMISO (2.56±0.77, 1.98±0.54), as compared to 18F-FETNIM (2.12±0.56, 1.42±0.33) were seen in tumor, P = 0.022, <0.001. For the patients with different histopathological subtypes, no significant difference of SUV (or T/B ratio) was observed both in 18F-FMISO and 18F-FETNIM in tumor. A significantly different SUV (or T/B ratio) was detected between < = 2cm, 2~5cm, and >5cm groups in 18F-FMISO PET/CT, P = 0.015 (or P = 0.029), whereas no difference was detected in 18F-FMISO PET/CT, P = 0.446 (or P = 0.707). Both 18F-FETNIM and 18F-FMISO showed significantly higher SUVs (or T/B ratios) in stage IV than stage III, P = 0.021, 0.013 (or P = 0.032, 0.02). Conclusion 18F-FMISO showed significantly higher uptake than 18F-FETNIM in tumor/non-tumor ratio and might be a better hypoxia tracer in lung cancer. PMID:27322586

  17. 18F-FDG PET/CT Imaging of Extranodal Rosai-Dorfman Disease with Hepatopancreatic Involvement - A Pictorial and Literature Review

    PubMed Central

    Awan, Omer; Mohiuddin, Sohaib; Farooqui, Saleem; Khan, Salman A; McCartney, William

    2015-01-01

    We share our experience with serial PET/CT imaging on a patient with extranodal Rosai-Dorfman disease (RDD) with hepatopancreatic involvement. RDD is a benign proliferative disorder of histiocytes mainly involving the lymph nodes. It typically presents with fever and painless cervical lymphadenopathy in young adults and less than half of RDS cases demonstrate extranodal involvement. RDD involvement of the liver and pancreas is extremely rare, and this case highlights the role of PET/CT in its management. PMID:26798568

  18. 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.

  19. TU-AB-BRA-06: Texture Feature Reproducibility Between PET/CT and PET/MR Imaging Modalities

    SciTech Connect

    Galavis, P; Friedman, K; Chandarana, H; Jackson, K

    2015-06-15

    Purpose: Radiomics involves the extraction of texture features from different imaging modalities with the purpose of developing models to predict patient treatment outcomes. The purpose of this study is to investigate texture feature reproducibility across [18F]FDG PET/CT and [18F]FDG PET/MR imaging in patients with primary malignancies. Methods: Twenty five prospective patients with solid tumors underwent clinical [18F]FDG PET/CT scan followed by [18F]FDG PET/MR scans. In all patients the lesions were identified using nuclear medicine reports. The images were co-registered and segmented using an in-house auto-segmentation method. Fifty features, based on the intensity histogram, second and high order matrices, were extracted from the segmented regions from both image data sets. One-way random-effects ANOVA model of the intra-class correlation coefficient (ICC) was used to establish texture feature correlations between both data sets. Results: Fifty features were classified based on their ICC values, which were found in the range from 0.1 to 0.86, in three categories: high, intermediate, and low. Ten features extracted from second and high-order matrices showed large ICC ≥ 0.70. Seventeen features presented intermediate 0.5 ≤ ICC ≤ 0.65 and the remaining twenty three presented low ICC ≤ 0.45. Conclusion: Features with large ICC values could be reliable candidates for quantification as they lead to similar results from both imaging modalities. Features with small ICC indicates a lack of correlation. Therefore, the use of these features as a quantitative measure will lead to different assessments of the same lesion depending on the imaging modality from where they are extracted. This study shows the importance of the need for further investigation and standardization of features across multiple imaging modalities.

  20. A method of semi-quantifying β-AP in brain PET-CT 11C-PiB images.

    PubMed

    Jiang, Jiehui; Lin, Xiaoman; Wen, Junlin; Huang, Zhemin; Yan, Zhuangzhi

    2014-01-01

    Alzheimer's disease (AD) is a common health problem for elderly populations. Positron emission tomography-computed tomography (PET-CT)11C-PiB for beta-P (amyloid-β peptide, β-AP) imaging is an advanced method to diagnose AD in early stage. However, in practice radiologists lack a standardized value to semi-quantify β-AP. This paper proposes such a standardized value: SVβ-AP. This standardized value measures the mean ratio between the dimension of β-AP areas in PET and CT images. A computer aided diagnosis approach is also proposed to achieve SVβ-AP. A simulation experiment was carried out to pre-test the technical feasibility of the CAD approach and SVβ-AP. The experiment results showed that it is technically feasible.

  1. MO-G-17A-08: Applications of Quantitative PET/CT Imaging of Yttrium-90: A Tool for Improving Radioembolization

    SciTech Connect

    Pasciak, A; Bradley, Y

    2014-06-15

    Purpose: Yttrium-90 (Y90) PET/CT post-treatment imaging of radioembolization has fostered significant interest from both the interventional radiology and nuclear medicine communities over the past few years. Recent literature has demonstrated high quantitative accuracy of Y90 PET at the activity concentrations common in radioembolization. However, few have explored methods in which this information can be clinically applied toward improving patient care. Methods: IRB approval and informed consent was obtained for over 35 Y90 post-treatment imaging studies, performed under 2 distinct protocols. In protocol 1, Y90 PET/CT provided quantitative post-treatment imaging, which was then converted into 3D maps of absorbed-dose. Both images and absorbed dose maps were used to manage patient care. In protocol 2, tumor absorbed-dose measurements from Y90 PET/CT were compared to known tumoricidal thresholds. If insufficient absorbed dose was delivered to the tumor, the patient would have an additional Y90 infusion the same day, providing truly patient-specific Y90 PET/CT based treatment-planning. Results: Y90 PET/CT allowed for a superior post-radioembolization evaluation of technical success compared with conventional Y90 bremsstrahlung SPECT. Due to the exceptional resolution of PET, a direct comparison between the distribution of radioembolization and pre-treatment planning intentions can be made. Further, quantification of tumor absorbed-dose directly from PET/CT imaging allows for the prediction of treatment efficacy based on a comparison with known tumoricidal thresholds. This immediate evaluation allowed treating physicians to consider additional or alternate therapies before discovering clinical failure weeks later. One protocol 2 patient was found to have a subtumoricidal absorbed dose following radioembolization. This patient received a same-day infusion of additional Y90 with identical catheter placement to the first infusion. A robust treatment response was seen on

  2. Clinical application of in vivo treatment delivery verification based on PET/CT imaging of positron activity induced at high energy photon therapy

    NASA Astrophysics Data System (ADS)

    Janek Strååt, Sara; Andreassen, Björn; Jonsson, Cathrine; Noz, Marilyn E.; Maguire, Gerald Q., Jr.; Näfstadius, Peder; Näslund, Ingemar; Schoenahl, Frederic; Brahme, Anders

    2013-08-01

    The purpose of this study was to investigate in vivo verification of radiation treatment with high energy photon beams using PET/CT to image the induced positron activity. The measurements of the positron activation induced in a preoperative rectal cancer patient and a prostate cancer patient following 50 MV photon treatments are presented. A total dose of 5 and 8 Gy, respectively, were delivered to the tumors. Imaging was performed with a 64-slice PET/CT scanner for 30 min, starting 7 min after the end of the treatment. The CT volume from the PET/CT and the treatment planning CT were coregistered by matching anatomical reference points in the patient. The treatment delivery was imaged in vivo based on the distribution of the induced positron emitters produced by photonuclear reactions in tissue mapped on to the associated dose distribution of the treatment plan. The results showed that spatial distribution of induced activity in both patients agreed well with the delivered beam portals of the treatment plans in the entrance subcutaneous fat regions but less so in blood and oxygen rich soft tissues. For the preoperative rectal cancer patient however, a 2 ± (0.5) cm misalignment was observed in the cranial-caudal direction of the patient between the induced activity distribution and treatment plan, indicating a beam patient setup error. No misalignment of this kind was seen in the prostate cancer patient. However, due to a fast patient setup error in the PET/CT scanner a slight mis-position of the patient in the PET/CT was observed in all three planes, resulting in a deformed activity distribution compared to the treatment plan. The present study indicates that the induced positron emitters by high energy photon beams can be measured quite accurately using PET imaging of subcutaneous fat to allow portal verification of the delivered treatment beams. Measurement of the induced activity in the patient 7 min after receiving 5 Gy involved count rates which were about

  3. Variations in PET/CT Methodology for Oncologic Imaging at U.S. Academic Medical Centers: An Imaging Response Assessment Team Survey

    PubMed Central

    Graham, Michael M.; Badawi, Ramsey D.; Wahl, Richard L.

    2014-01-01

    In 2005, 8 Imaging Response Assessment Teams (IRATs) were funded by the National Cancer Institute (NCI) as supplemental grants to existing NCI Cancer Centers. After discussion among the IRATs regarding the need for increased standardization of clinical and research PET/CT methodology, it became apparent that data acquisition and processing approaches differ considerably among centers. To determine the variability in detail, a survey of IRAT sites and IRAT affiliates was performed. Methods A 34-question instrument evaluating patient preparation, scanner type, performance approach, display, and analysis was developed. Fifteen institutions, including the 8 original IRATs and 7 institutions that had developed affiliate IRATs, were surveyed. Results The major areas of variation were18F-FDG dose (259–740 MBq [7–20 mCi]) uptake time (45–90 min), sedation (never to frequently), handling of diabetic patients, imaging time (2–7 min/bed position), performance of diagnostic CT scans as a part of PET/CT, type of acquisition (2-dimensional vs. 3-dimensional), CT technique, duration of fasting (4 or 6 h), and (varying widely) acquisition, processing, display, and PACS software—with 4 sites stating that poor-quality images appear on PACS. Conclusion There is considerable variability in the way PET/CT scans are performed at academic institutions that are part of the IRAT network. This variability likely makes it difficult to quantitatively compare studies performed at different centers. These data suggest that additional standardization in methodology will be required so that PET/CT studies, especially those performed quantitatively, are more comparable across sites. PMID:21233185

  4. Initial Fludeoxyglucose (18F) Positron Emission Tomography-Computed Tomography (FDG-PET/CT) Imaging of Breast Cancer – Correlations with the Primary Tumour and Locoregional Metastases

    PubMed Central

    Ayaz, Sevin; Gültekin, Salih Sinan; Ayaz, Ümit Yaşar; Dilli, Alper

    2017-01-01

    Summary Backround We aimed to evaluate initial PET/CT features of primary tumour and locoregional metastatic lymph nodes (LNs) in breast cancer and to look for potential relationships between several parameters from PET/CT. Material/Methods Twenty-three women (mean age; 48.66±12.23 years) with a diagnosis of primary invasive ductal carcinoma were included. They underwent PET/CT imaging for the initial tumour staging and had no evidence of distant metastates. Patients were divided into two groups. The LABC (locally advanced breast cancer) group included 17 patients with ipsilateral axillary lymph node (LN) metastases. The Non-LABC group consisted of six patients without LN metastases. PET/CT parameters including tumour size, axillary LN size, SUVmax of ipsilateral axillary LNs (SUVmax-LN), SUVmax of primary tumour (SUVmax-T) and NT ratios (SUVmax-LN/SUVmax-T) were compared between the groups. Correlations between the above-mentioned PET/CT parameters in the LABC group as well as the correlation between tumour size and SUVmax-T within each group were evaluated statistically. Results The mean values of the initial PET/CT parameters in the LABC group were significantly higher than those of the non-LABC group (p<0.05). The correlation between tumour size and SUVmax-T value within both LABC and non-LABC groups was statistically significant (p<0.05). In the LABC group, the correlations between the size and SUVmax-LN values of metastatic axillary LNs, between tumour size and metastatic axillary LN size, between SUVmax-T values and metastatic axillary LN size, between SUVmax-T and SUVmax-LN values, and between tumour size and SUVmax-LN values were all significant (p<0.05). Conclusions We found significant correlations between PET/CT parameters of the primary tumour and those of metastatic axillary LNs. Patients with LN metastases had relatively larger primary tumours and higher SUVmax values. PMID:28105247

  5. PSMA-PET/CT-Positive Paget Disease in a Patient with Newly Diagnosed Prostate Cancer: Imaging and Bone Biopsy Findings.

    PubMed

    Froehner, Michael; Toma, Marieta; Zöphel, Klaus; Novotny, Vladimir; Laniado, Michael; Wirth, Manfred P

    2017-01-01

    A 67-year-old man diagnosed with Gleason score 4 + 5 = 9 clinically localized prostate cancer with (68)Ga-labeled prostate-specific membrane antigen-targeted ligand positron emission tomography/computed tomography (PSMA-PET/CT) positive Paget bone disease is described. Immunohistochemical staining revealed weak PSMA positivity of the bone lesion supporting the hypothesis that neovasculature might explain positive PSMA-PET/CT findings in Paget disease.

  6. PSMA-PET/CT-Positive Paget Disease in a Patient with Newly Diagnosed Prostate Cancer: Imaging and Bone Biopsy Findings

    PubMed Central

    Toma, Marieta; Zöphel, Klaus; Novotny, Vladimir; Laniado, Michael

    2017-01-01

    A 67-year-old man diagnosed with Gleason score 4 + 5 = 9 clinically localized prostate cancer with 68Ga-labeled prostate-specific membrane antigen-targeted ligand positron emission tomography/computed tomography (PSMA-PET/CT) positive Paget bone disease is described. Immunohistochemical staining revealed weak PSMA positivity of the bone lesion supporting the hypothesis that neovasculature might explain positive PSMA-PET/CT findings in Paget disease.

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

    SciTech Connect

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

    2012-08-01

    Purpose: To investigate the additional value of {sup 11}C-choline positron emission tomography (PET)-computed tomography (CT) to T2-weighted (T2w) magnetic resonance imaging (MRI) for localization of intraprostatic tumor nodules. Methods and Materials: Forty-nine prostate cancer patients underwent T2w MRI and {sup 11}C-choline PET-CT before radical prostatectomy and extended lymphadenectomy. Tumor regions were outlined on the whole-mount histopathology sections and on the T2w MR images. Tumor localization was recorded in the basal, middle, and apical part of the prostate by means of an octant grid. To analyze {sup 11}C-choline PET-CT images, the same grid was used to calculate the standardized uptake values (SUV) per octant, after rigid registration with the T2w MR images for anatomic reference. Results: In total, 1,176 octants were analyzed. Sensitivity, specificity, and accuracy of T2w MRI were 33.5%, 94.6%, and 70.2%, respectively. For {sup 11}C-choline PET-CT, the mean SUV{sub max} of malignant octants was significantly higher than the mean SUV{sub max} of benign octants (3.69 {+-} 1.29 vs. 3.06 {+-} 0.97, p < 0.0001) which was also true for mean SUV{sub mean} values (2.39 {+-} 0.77 vs. 1.94 {+-} 0.61, p < 0.0001). A positive correlation was observed between SUV{sub mean} and absolute tumor volume (Spearman r = 0.3003, p = 0.0362). No correlation was found between SUVs and prostate-specific antigen, T-stage or Gleason score. The highest accuracy (61.1%) was obtained with a SUV{sub max} cutoff of 2.70, resulting in a sensitivity of 77.4% and a specificity of 44.9%. When both modalities were combined (PET-CT or MRI positive), sensitivity levels increased as a function of SUV{sub max} but at the cost of specificity. When only considering suspect octants on {sup 11}C-choline PET-CT (SUV{sub max} {>=} 2.70) and T2w MRI, 84.7% of these segments were in agreement with the gold standard, compared with 80.5% for T2w MRI alone. Conclusions: The additional value of {sup

  8. Topology polymorphism graph for lung tumor segmentation in PET-CT images

    NASA Astrophysics Data System (ADS)

    Cui, Hui; Wang, Xiuying; Zhou, Jianlong; Eberl, Stefan; Yin, Yong; Feng, Dagan; Fulham, Michael

    2015-06-01

    Accurate lung tumor segmentation is problematic when the tumor boundary or edge, which reflects the advancing edge of the tumor, is difficult to discern on chest CT or PET. We propose a ‘topo-poly’ graph model to improve identification of the tumor extent. Our model incorporates an intensity graph and a topology graph. The intensity graph provides the joint PET-CT foreground similarity to differentiate the tumor from surrounding tissues. The topology graph is defined on the basis of contour tree to reflect the inclusion and exclusion relationship of regions. By taking into account different topology relations, the edges in our model exhibit topological polymorphism. These polymorphic edges in turn affect the energy cost when crossing different topology regions under a random walk framework, and hence contribute to appropriate tumor delineation. We validated our method on 40 patients with non-small cell lung cancer where the tumors were manually delineated by a clinical expert. The studies were separated into an ‘isolated’ group (n = 20) where the lung tumor was located in the lung parenchyma and away from associated structures / tissues in the thorax and a ‘complex’ group (n = 20) where the tumor abutted / involved a variety of adjacent structures and had heterogeneous FDG uptake. The methods were validated using Dice’s similarity coefficient (DSC) to measure the spatial volume overlap and Hausdorff distance (HD) to compare shape similarity calculated as the maximum surface distance between the segmentation results and the manual delineations. Our method achieved an average DSC of 0.881  ±  0.046 and HD of 5.311  ±  3.022 mm for the isolated cases and DSC of 0.870  ±  0.038 and HD of 9.370  ±  3.169 mm for the complex cases. Student’s t-test showed that our model outperformed the other methods (p-values <0.05).

  9. Role of MR Imaging and FDG PET/CT in Selection and Follow-up of Patients Treated with Pelvic Exenteration for Gynecologic Malignancies

    PubMed Central

    Nougaret, Stephanie; Miccò, Maura; Scelzo, Chiara; Vargas, Hebert A.; Sosa, Ramon E.; Sutton, Elizabeth J.; Chi, Dennis S.; Hricak, Hedvig; Sala, Evis

    2015-01-01

    Pelvic exenteration (PE) is a radical surgical procedure used for the past 6 decades to treat locally advanced malignant diseases confined to the pelvis, particularly persistent or recurrent gynecologic cancers in the irradiated pelvis. The traditional surgical technique known as total PE consists of resection of all pelvic viscera followed by reconstruction. Depending on the tumor extent, the procedure can be tailored to remove only anterior or posterior structures, including the bladder (anterior exenteration) or rectum (posterior exenteration). Conversely, more extended pelvic resection can be performed if the pelvic sidewall is invaded by cancer. Preoperative imaging evaluation with magnetic resonance (MR) imaging and fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) is central to establishing tumor resectability and therefore patient eligibility for the procedure. These imaging modalities complement each other in diagnosis of tumor recurrence and differentiation of persistent disease from posttreatment changes. MR imaging can accurately demonstrate local tumor extent and show adjacent organ invasion. FDG PET/CT is useful in excluding nodal and distant metastases. In addition, FDG PET/CT metrics may serve as predictive biomarkers for overall and disease-free survival. This pictorial review describes different types of exenterative surgical procedures and illustrates the central role of imaging in accurate patient selection, treatment planning, and postsurgical surveillance. ©RSNA, 2015 PMID:26172364

  10. 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.; ...

    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

  11. Random Walk and Graph Cut for Co-Segmentation of Lung Tumor on PET-CT Images.

    PubMed

    Ju, Wei; Xiang, Dehui; Xiang, Deihui; Zhang, Bin; Wang, Lirong; Kopriva, Ivica; Chen, Xinjian

    2015-12-01

    Accurate lung tumor delineation plays an important role in radiotherapy treatment planning. Since the lung tumor has poor boundary in positron emission tomography (PET) images and low contrast in computed tomography (CT) images, segmentation of tumor in the PET and CT images is a challenging task. In this paper, we effectively integrate the two modalities by making fully use of the superior contrast of PET images and superior spatial resolution of CT images. Random walk and graph cut method is integrated to solve the segmentation problem, in which random walk is utilized as an initialization tool to provide object seeds for graph cut segmentation on the PET and CT images. The co-segmentation problem is formulated as an energy minimization problem which is solved by max-flow/min-cut method. A graph, including two sub-graphs and a special link, is constructed, in which one sub-graph is for the PET and another is for CT, and the special link encodes a context term which penalizes the difference of the tumor segmentation on the two modalities. To fully utilize the characteristics of PET and CT images, a novel energy representation is devised. For the PET, a downhill cost and a 3D derivative cost are proposed. For the CT, a shape penalty cost is integrated into the energy function which helps to constrain the tumor region during the segmentation. We validate our algorithm on a data set which consists of 18 PET-CT images. The experimental results indicate that the proposed method is superior to the graph cut method solely using the PET or CT is more accurate compared with the random walk method, random walk co-segmentation method, and non-improved graph cut method.

  12. Dynamic Contrast-Enhanced Magnetic Resonance Imaging (DCE-MRI) Combined with Positron Emission Tomography-Computed Tomography (PET-CT) and Video-Electroencephalography (VEEG) Have Excellent Diagnostic Value in Preoperative Localization of Epileptic Foci in Children with Epilepsy

    PubMed Central

    Wang, Gui-Bin; Long, Wei; Li, Xiao-Dong; Xu, Guang-Yin; Lu, Ji-Xiang

    2017-01-01

    Background To investigate the effect that dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) has on surgical decision making relative to video-electroencephalography (VEEG) and positron emission tomography-computed tomography (PET-CT), and if the differences in these variables translates to differences in surgical outcomes. Material/Methods A total of 166 children with epilepsy undergoing preoperative DCE-MRI, VEEG, and PET-CT examinations, surgical resection of epileptic foci, and intraoperative electrocorticography (ECoG) monitoring were enrolled. All children were followed up for 12 months and grouped by Engles prognostic classification for epilepsy. Based on intraoperative ECoG as gold standard, the diagnostic values of DCE-MRI, VEEG, PET-CT, DCE-MRI combined with VEEG, DCE-MRI combined with PET-CT, and combined application of DCE-MRI, VEEG, and PET-CT in preoperative localization for epileptic foci were evaluated. Results The sensitivity of DCE-MRI, VEEG, and PET-CT was 59.64%, 76.51%, and 93.98%, respectively; the accuracy of DCE-MRI, VEEG, PET-CT, DCE-MRI combined with VEEG, and DCE-MRI combined with PET-CT was 57.58%, 67.72%, 91.03%, 91.23%, and 96.49%, respectively. Localization accuracy rate of the combination of DCE-MRI, VEEG, and PET-CT was 98.25% (56/57), which was higher than that of DCE-MRI combined with VEEG and of DCE-MRI combined with PET-CT. No statistical difference was found in the accuracy rate of localization between these three combined techniques. During the 12-month follow-up, children were grouped into Engles grade I (n=106), II (n=31), III (n=21), and IV (n=8) according to postoperative conditions. Conclusions All DCE-MRI combined with VEEG, DCE-MRI combined with PET-CT, and DCE-MRI combined with VEEG and PET-CT examinations have excellent accuracy in preoperative localization of epileptic foci and present excellent postoperative efficiency, suggesting that these combined imaging methods are suitable for serving as the

  13. Neurosarcoidosis on FET and FDG PET/CT.

    PubMed

    Chan, Mico; Hsiao, Edward

    2017-03-01

    O-(2-fluoroethyl)-L-tyrosine (FET) PET/CT is a promising imaging modality for brain tumor imaging because of its reported high sensitivity for biologically active tumor tissue. We present a case of biopsy-proven neurosarcoidosis showing FET uptake. It is an important cause of false-positive uptake on FET PET/CT.

  14. Automated localization and segmentation of lung tumor from PET-CT thorax volumes based on image feature analysis.

    PubMed

    Cui, Hui; Wang, Xiuying; Feng, Dagan

    2012-01-01

    Positron emission tomography - computed tomography (PET-CT) plays an essential role in early tumor detection, diagnosis, staging and treatment. Automated and more accurate lung tumor detection and delineation from PET-CT is challenging. In this paper, on the basis of quantitative analysis of contrast feature of PET volume in SUV (standardized uptake value), our method firstly automatically localized the lung tumor. Then based on analysing the surrounding CT features of the initial tumor definition, our decision strategy determines the tumor segmentation from CT or from PET. The algorithm has been validated on 20 PET-CT studies involving non-small cell lung cancer (NSCLC). Experimental results demonstrated that our method was able to segment the tumor when adjacent to mediastinum or chest wall, and the algorithm outperformed the other five lung segmentation methods in terms of overlapping measure.

  15. Spatial Resolution and Image Qualities of Zr-89 on Siemens Biograph TruePoint PET/CT

    PubMed Central

    Lee, Young Sub; Kim, Jung Young; Kim, Byung Il; Lim, Sang Moo; Kim, Hee-Joung

    2015-01-01

    Abstract Purpose: Zirconium-89 (t1/2=78.41 hours) is an ideal metallic radioisotope for immuno–positron emission tomography (PET), given that its physical half-life closely matches the biological half-life of monoclonal antibodies. In this study, the authors measured the spatial resolution and image quality of Zr-89 PET and compared the results against those obtained using F-18 PET, which is widely regarded as the gold standard for comparison of imaging characteristics. Materials and Methods: The spatial resolution and image qualities of Zr-89 were measured on the Siemens Biograph Truepoint TrueV PET/CT scanner, partly according to NEMA NU2-2007 standards. For spatial resolution measurement, the Zr-89 point source was located at the center of the axial field of view (FOV) and offset 1/4 axial FOV from the center. For image quality measurements, an NEMA IEC Phantom was used. The NEMA IEC Phantom consists of six hot spheres that were filled with Zr-89 solution. Spatial resolution and image quality (%contrast, %background variability [BV], and source to background ratio [SBR]) were assessed to compare the imaging characteristics of F-18 with those of Siemens Biograph Truepoint TrueV. Results: The transverse and axial spatial resolutions at 1 cm were 4.5 and 4.7 mm for Zr-89, respectively. The %contrast of Zr-89 was 25.5% for the smallest 10 mm sized sphere and 89.8% for the largest 37 mm sized sphere, and for F-18, it was 32.5% for the smallest 10 mm sized sphere and 103.9% for the largest 37 mm sized sphere using the ordered subset expectation maximization (OSEM) reconstruction method. The %BV of F-18 PET was 6.4% for the smallest 10 mm sized sphere and 3.5% for the largest 37 mm sized sphere using the OSEM reconstruction. The SBR of Zr-89 was 1.8 for the smallest 10 mm sized sphere and 3.7 for the largest 37 mm sized sphere, and for F-18, it was 2.0 for the smallest 10 mm sized sphere and 4.1 for the largest 37 mm sized sphere using the

  16. The scope and potentials of functional radionuclide imaging towards advancing personalized medicine in oncology: emphasis on PET-CT.

    PubMed

    Basu, Sandip

    2012-01-01

    Behavioral heterogeneity within a given patient cohort has been a major challenge in clinical practice and is probably most prominently observed in the field of oncology. This has been the prime impetus of the cutting-edge preclinical and clinical research studies over recent times, many of which seek to further stratify patients based on patients' genetic, proteomic, and metabolic profile (the three key components of "-omics" research), in order to select the appropriate therapy according to an individual's best-fit. Data from functional radionuclide imaging particularly that obtained from PET-CT, with regard to characterization of an individual's tumor phenotype, can play a very important role in answering some of the critical decision-making questions on an individual basis. The role of molecular imaging with PET, SPECT, and planar radionuclide technologies is not confined to early response assessment of administered therapeutics (which is its major benefit compared to conventional methods), rather it has a much broader perspective and encompasses multiple steps in decision making steps of patient management. The immense impact of the radionuclide-based molecular imaging techniques on the selection of an appropriate treatment (at initial diagnosis, during therapy, or after therapy) or in defining the tumor biology has been documented and increasingly recognized through both large and small-scale studies. However, there has been relatively less systematic effort towards the development of a successful and definitive clinical model of "personalized cancer medicine" (based on accurate disease triaging on an individual basis) by the medical community that would be suitable for routine adoption. In this paper, an endeavor has been made to explore the potential of this approach and underscore the areas that would require further critical evaluation to make this a reality.

  17. A computational pipeline for quantification of pulmonary infections in small animal models using serial PET-CT imaging

    PubMed Central

    2013-01-01

    agreements (all above 85%) with expert evaluations for both structural and functional imaging modalities. Apart from quantitative analysis of each animal, we also qualitatively showed how metabolic volumes were changing over time by examining serial PET/CT scans. Evaluation of the registration processes was based on precisely defined anatomical landmark points by expert clinicians. An average of 2.66, 3.93, and 2.52 mm errors was found in rabbit, ferret, and mouse data (all within the resolution limits), respectively. Quantitative results obtained from the proposed methodology were visually related to the progress and severity of the pulmonary infections as verified by the participating radiologists. Moreover, we demonstrated that lesions due to the infections were metabolically active and appeared multi-focal in nature, and we observed similar patterns in the CT images as well. Consolidation and ground glass opacity were the main abnormal imaging patterns and consistently appeared in all CT images. We also found that the gross and metabolic lesion volume percentage follow the same trend as the SUV-based evaluation in the longitudinal analysis. Conclusions We explored the feasibility of using PET and CT imaging modalities in three distinct small animal models for two diverse pulmonary infections. We concluded from the clinical findings, derived from the proposed computational pipeline, that PET-CT imaging is an invaluable hybrid modality for tracking pulmonary infections longitudinally in small animals and has great potential to become routinely used in clinics. Our proposed methodology showed that automated computed-aided lesion detection and quantification of pulmonary infections in small animal models are efficient and accurate as compared to the clinical standard of manual and semi-automated approaches. Automated analysis of images in pre-clinical applications can increase the efficiency and quality of pre-clinical findings that ultimately inform downstream experimental

  18. Design of an Image Fusion Phantom for a Small Animal microPET/CT Scanner Prototype

    NASA Astrophysics Data System (ADS)

    Nava-García, Dante; Alva-Sánchez, Héctor; Murrieta-Rodríguez, Tirso; Martínez-Dávalos, Arnulfo; Rodríguez-Villafuerte, Mercedes

    2010-12-01

    Two separate microtomography systems recently developed at Instituto de Física, UNAM, produce anatomical (microCT) and physiological images (microPET) of small animals. In this work, the development and initial tests of an image fusion method based on fiducial markers for image registration between the two modalities are presented. A modular Helix/Line-Sources phantom was designed and constructed; this phantom contains fiducial markers that can be visualized in both imaging systems. The registration was carried out by solving the rigid body alignment problem of Procrustes to obtain rotation and translation matrices required to align the two sets of images. The microCT/microPET image fusion of the Helix/Line-Sources phantom shows excellent visual coincidence between different structures, showing a calculated target-registration-error of 0.32 mm.

  19. F18 EF5 PET/CT Imaging in Patients with Brain Metastases from Breast Cancer

    DTIC Science & Technology

    2012-07-01

    disease . One had progressive lung disease limiting her ability to lay supine for imaging, and the second patient developed leptomeningeal spread...patient developed progressive leptomeningeal disease and required spinal radiation leaving her fatigued and unable to complete the study. A third patient...of her disease and declined further imaging studies. A third patient has been enrolled and is scheduled for imaging later in August 2012. 15

  20. Quantitative Imaging Analysis of FDG PET/CT Imaging for Detection of Central Neurolymphomatosis in a Case of Recurrent Diffuse B-Cell Lymphoma.

    PubMed Central

    Savells, Derek; Awan, Omer; Inayat, Faisal; Chaudhry, Ammar; Jerath, Nivedita; Graham, Michael M

    2015-01-01

    Neurolymphomatosis (NL) is a rare disease characterized by malignant lymphocytes infiltrating various structures of the nervous system. It typically manifests as a neuropathy involving the peripheral nerves, nerve roots, plexuses, or cranial nerves. It often presents as a complication of lymphoma, but it can be the presenting feature of recurrent lymphoma. It is essential to identify and initiate treatment early with chemotherapy and/or radiation therapy in all cases of nodal or visceral (including neural) involvement with lymphoma. There are various diagnostic tests that can be used for its detection, such as cerebrospinal spinal fluid (CSF) cytology, electromyography (EMG), magnetic resonance imaging (MRI), and positron-emission tomography/computed tomography (PET/CT). FDG-PET/CT is the standard of care in lymphoma staging, restaging, and therapy response assessment, but has an inherent limitation in the detection of disease involvement in the central nervous system. While that is mostly true for visual assessment, there are quantitative methods to measure variation in the metabolic activity in the brain, which in turn helps detect the occurrence of neurolymphomatosis. PMID:26719822

  1. EXPLORER: Changing the molecular imaging paradigm with total-body PET/CT (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Cherry, Simon R.; Badawi, Ramsey D.; Jones, Terry

    2016-04-01

    Positron emission tomography (PET) is the highest sensitivity technique for human whole-body imaging studies. However, current clinical PET scanners do not make full use of the available signal, as they only permit imaging of a 15-25 cm segment of the body at one time. Given the limited sensitive region, whole-body imaging with clinical PET scanners requires relatively long scan times and subjects the patient to higher than necessary radiation doses. The EXPLORER initiative aims to build a 2-meter axial length PET scanner to allow imaging the entire subject at once, capturing nearly the entire available PET signal. EXPLORER will acquire data with ~40-fold greater sensitivity leading to a six-fold increase in reconstructed signal-to-noise ratio for imaging the total body. Alternatively, total-body images with the EXPLORER scanner will be able to be acquired in ~30 seconds or with ~0.15 mSv injected dose, while maintaining current PET image quality. The superior sensitivity will open many new avenues for biomedical research. Specifically for cancer applications, high sensitivity PET will enable detection of smaller lesions. Additionally, greater sensitivity will allow imaging out to 10 half-lives of positron emitting radiotracers. This will enable 1) metabolic ultra-staging with FDG by extending the uptake and clearance time to 3-5 hours to significantly improve contrast and 2) improved kinetic imaging with short-lived radioisotopes such as C-11, crucial for drug development studies. Frequent imaging studies of the same subject to study disease progression or to track response to therapy will be possible with the low dose capabilities of the EXPLORER scanner. The low dose capabilities will also open up new imaging possibilities in pediatrics and adolescents to better study developmental disorders. This talk will review the basis for developing total-body PET, potential applications, and review progress to date in developing EXPLORER, the first total-body PET scanner.

  2. Computerized PET/CT image analysis in the evaluation of tumour response to therapy

    PubMed Central

    Wang, J; Zhang, H H

    2015-01-01

    Current cancer therapy strategy is mostly population based, however, there are large differences in tumour response among patients. It is therefore important for treating physicians to know individual tumour response. In recent years, many studies proposed the use of computerized positron emission tomography/CT image analysis in the evaluation of tumour response. Results showed that computerized analysis overcame some major limitations of current qualitative and semiquantitative analysis and led to improved accuracy. In this review, we summarize these studies in four steps of the analysis: image registration, tumour segmentation, image feature extraction and response evaluation. Future works are proposed and challenges described. PMID:25723599

  3. [18F]FHBG PET/CT Imaging of CD34-TK75 Transduced Donor T Cells in Relapsed Allogeneic Stem Cell Transplant Patients: Safety and Feasibility

    PubMed Central

    Eissenberg, Linda G; Rettig, Michael P; Ritchey, Julie K; Prior, Julie L; Schwarz, Sally W; Frye, Jennifer; White, Brian S; Fulton, Robert S; Ghobadi, Armin; Cooper, Matthew L; Couriel, Daniel R; Seegulam, Muhammad Esa; Piwnica-Worms, David; Dehdashti, Farrokh; Cornetta, Kenneth; DiPersio, John F

    2015-01-01

    Described herein is a first-in-man attempt to both genetically modify T cells with an imagable suicide gene and track these transduced donor T cells in allogeneic stem cell transplantation recipients using noninvasive positron emission tomography/computerized tomography (PET/CT) imaging. A suicide gene encoding a human CD34-Herpes Simplex Virus-1-thymidine kinase (CD34-TK75) fusion enabled enrichment of retrovirally transduced T cells (TdT), control of graft-versus-host disease and imaging of TdT migration and expansion in vivo in mice and man. Analysis confirmed that CD34-TK75-enriched TdT contained no replication competent γ-retrovirus, were sensitive to ganciclovir, and displayed characteristic retroviral insertion sites (by targeted sequencing). Affinity-purified CD34-TK75+-selected donor T cells (1.0–13 × 105)/kg were infused into eight patients who relapsed after allogeneic stem cell transplantation. Six patients also were administered 9-[4-(18F)fluoro-3-hydroxymethyl-butyl]guanine ([18F]FHBG) to specifically track the genetically modified donor T cells by PET/CT at several time points after infusion. All patients were assessed for graft-versus-host disease, response to ganciclovir, circulating TdT cells (using both quantitative polymerase chain reaction and [18F]FHBG PET/CT imaging), TdT cell clonal expansion, and immune response to the TdT. This phase 1 trial demonstrated that genetically modified T cells and [18F]FHBG can be safely infused in patients with relapsed hematologic malignancies after allogeneic stem cell transplantation. PMID:25807290

  4. Accuracy of CT-based attenuation correction in PET/CT bone imaging.

    PubMed

    Abella, Monica; Alessio, Adam M; Mankoff, David A; MacDonald, Lawrence R; Vaquero, Juan Jose; Desco, Manuel; Kinahan, Paul E

    2012-05-07

    We evaluate the accuracy of scaling CT images for attenuation correction of PET data measured for bone. While the standard tri-linear approach has been well tested for soft tissues, the impact of CT-based attenuation correction on the accuracy of tracer uptake in bone has not been reported in detail. We measured the accuracy of attenuation coefficients of bovine femur segments and patient data using a tri-linear method applied to CT images obtained at different kVp settings. Attenuation values at 511 keV obtained with a (68)Ga/(68)Ge transmission scan were used as a reference standard. The impact of inaccurate attenuation images on PET standardized uptake values (SUVs) was then evaluated using simulated emission images and emission images from five patients with elevated levels of FDG uptake in bone at disease sites. The CT-based linear attenuation images of the bovine femur segments underestimated the true values by 2.9 ± 0.3% for cancellous bone regardless of kVp. For compact bone the underestimation ranged from 1.3% at 140 kVp to 14.1% at 80 kVp. In the patient scans at 140 kVp the underestimation was approximately 2% averaged over all bony regions. The sensitivity analysis indicated that errors in PET SUVs in bone are approximately proportional to errors in the estimated attenuation coefficients for the same regions. The variability in SUV bias also increased approximately linearly with the error in linear attenuation coefficients. These results suggest that bias in bone uptake SUVs of PET tracers ranges from 2.4% to 5.9% when using CT scans at 140 and 120 kVp for attenuation correction. Lower kVp scans have the potential for considerably more error in dense bone. This bias is present in any PET tracer with bone uptake but may be clinically insignificant for many imaging tasks. However, errors from CT-based attenuation correction methods should be carefully evaluated if quantitation of tracer uptake in bone is important.

  5. Accuracy of CT-Based Attenuation Correction in PET/CT Bone Imaging

    PubMed Central

    Abella, Monica; Alessio, Adam M.; Mankoff, David A.; MacDonald, Lawrence R.; Vaquero, Juan Jose; Desco, Manuel; Kinahan, Paul E.

    2012-01-01

    We evaluate the accuracy of scaling CT images for attenuation correction of PET data measured for bone. While the standard tri-linear approach has been well-tested for soft tissues, the impact of CT-based attenuation correction on the accuracy of tracer uptake in bone has not been reported in detail. We measured the accuracy of attenuation coefficients of bovine femur segments and patient data using a tri-linear method applied to CT images obtained at different kVp settings. Attenuation values at 511 keV obtained with a 68Ga/68Ge transmission scan were used as a reference standard. The impact of inaccurate attenuation images on PET standardized uptake values (SUVs) was then evaluated using simulated emission images and emission images from five patients with elevated levels of FDG uptake in bone at disease sites. The CT-based linear attenuation images of the bovine femur segments underestimated the true values by 2.9±0.3% for cancellous bone regardless of kVp. For compact bone the underestimation ranged from 1.3% at 140 kVp to 14.1% at 80 kVp. In the patient scans at 140 kVp the underestimation was approximately 2% averaged over all bony regions. The sensitivity analysis indicated that errors in PET SUVs in bone are approximately proportional to errors in the estimated attenuation coefficients for the same regions. The variability in SUV bias also increased approximately linearly with the error in linear attenuation coefficients. These results suggest that bias in bone uptake SUVs of PET tracers range from 2.4% to 5.9% when using CT scans at 140 and 120 kVp for attenuation correction. Lower kVp scans have the potential for considerably more error in dense bone. This bias is present in any PET tracer with bone uptake but may be clinically insignificant for many imaging tasks. However, errors from CT-based attenuation correction methods should be carefully evaluated if quantitation of tracer uptake in bone is important. PMID:22481547

  6. Evaluation of respiratory and cardiac motion correction schemes in dual gated PET/CT cardiac imaging

    SciTech Connect

    Lamare, F. Fernandez, P.; Le Maitre, A.; Visvikis, D.; Dawood, M.; Schäfers, K. P.; Rimoldi, O. E.

    2014-07-15

    Purpose: Cardiac imaging suffers from both respiratory and cardiac motion. One of the proposed solutions involves double gated acquisitions. Although such an approach may lead to both respiratory and cardiac motion compensation there are issues associated with (a) the combination of data from cardiac and respiratory motion bins, and (b) poor statistical quality images as a result of using only part of the acquired data. The main objective of this work was to evaluate different schemes of combining binned data in order to identify the best strategy to reconstruct motion free cardiac images from dual gated positron emission tomography (PET) acquisitions. Methods: A digital phantom study as well as seven human studies were used in this evaluation. PET data were acquired in list mode (LM). A real-time position management system and an electrocardiogram device were used to provide the respiratory and cardiac motion triggers registered within the LM file. Acquired data were subsequently binned considering four and six cardiac gates, or the diastole only in combination with eight respiratory amplitude gates. PET images were corrected for attenuation, but no randoms nor scatter corrections were included. Reconstructed images from each of the bins considered above were subsequently used in combination with an affine or an elastic registration algorithm to derive transformation parameters allowing the combination of all acquired data in a particular position in the cardiac and respiratory cycles. Images were assessed in terms of signal-to-noise ratio (SNR), contrast, image profile, coefficient-of-variation (COV), and relative difference of the recovered activity concentration. Results: Regardless of the considered motion compensation strategy, the nonrigid motion model performed better than the affine model, leading to higher SNR and contrast combined with a lower COV. Nevertheless, when compensating for respiration only, no statistically significant differences were

  7. Diagnosis, PET/CT imaging, and treatment of extranodal non-Hodgkin lymphoma in keratinized gingiva: a case report.

    PubMed

    Aral, Cüneyt A; Ağlarcı, Osman S; Yılmaz, Hasan H; Taşlı, Funda; Karaarslan, Serap; Hatipoğlu, Filiz; Sanal, Mustafa S

    2015-03-01

    A 58-year-old patient who smoked and had uncontrolled type 2 diabetes mellitus was referred to our clinic. The patient had a suspicious asymptomatic lesion that was diagnosed as B-cell non-Hodgkin lymphoma (NHL). Immunohistochemistry revealed intense and diffuse expression of CD20, CD10, BCL-6, and Ki-67. A positron emission tomography/computed tomography (PET/CT) scan showed focal pathological uptake of F-18-fluorodeoxyglucose only in the subcutaneous tissue anterior to the left maxillary sinus. After lesion excision and five courses of chemotherapy, PET/CT scans demonstrated complete resolution of the lesion. Smoking, uncontrolled diabetes mellitus, and periodontal disease might be predisposing factors for oral NHL.

  8. Rapidly growing complex fibroadenoma with surrounding ductal hyperplasia mimics breast malignancy on serial F-18 FDG PET/CT imaging.

    PubMed

    Makis, William; Ciarallo, Anthony; Hickeson, Marc; Derbekyan, Vilma

    2011-07-01

    A 30-year-old woman was referred for an F-18 fluorodeoxyglucose (FDG) PET/CT to rule out lymphoma, and was found to have an incidental FDG-avid right breast nodule that grew significantly in size and FDG uptake on a subsequent scan, raising suspicion of a growing breast malignancy. Histologic evaluation showed a complex fibroadenoma with adenosis and surrounding ductal hyperplasia. Although variable F-18 FDG uptake in fibroadenomas has been described, a distinction between simple and complex fibroadenomas has not been made in the PET literature, even though complex fibroadenomas have a higher propensity to develop into malignancies. This case shows that a rapidly growing complex fibroadenoma can mimic a breast malignancy on serial F-18 FDG PET/CT scans, showing significant increase in both size and FDG-avidity on follow-up studies.

  9. Multitracer Molecular Imaging of Paget Disease Targeting Bone Remodeling, Fatty Acid Metabolism, and PSMA Expression on PET/CT.

    PubMed

    Derlin, Thorsten; Weiberg, Desiree; Sohns, Jan M

    2016-12-01

    Paget disease is a chronic disorder resulting in enlarged and misshapen bones, and is caused by disorganized bone remodeling. We present the case of an 85-year-old man with prostatic adenocarcinoma and known Paget disease of the right iliac bone who underwent Ga-prostate-specific membrane antigen ligand, C-acetate, and F-fluoride PET/CT for restaging of cancer. On all PET scans, increased tracer accumulation was observed in Paget disease of bone. Besides that Paget disease may mimic metastases on PET/CT using various radiotracers, including Ga-prostate-specific membrane antigen ligands and C-acetate, this case highlights the potential of multiparametric disease characterization on PET.

  10. Local respiratory motion correction for PET/CT imaging: Application to lung cancer

    SciTech Connect

    Lamare, F. Fernandez, P.; Fayad, H.; Visvikis, D.

    2015-10-15

    Purpose: Despite multiple methodologies already proposed to correct respiratory motion in the whole PET imaging field of view (FOV), such approaches have not found wide acceptance in clinical routine. An alternative can be the local respiratory motion correction (LRMC) of data corresponding to a given volume of interest (VOI: organ or tumor). Advantages of LRMC include the use of a simple motion model, faster execution times, and organ specific motion correction. The purpose of this study was to evaluate the performance of LMRC using various motion models for oncology (lung lesion) applications. Methods: Both simulated (NURBS based 4D cardiac-torso phantom) and clinical studies (six patients) were used in the evaluation of the proposed LRMC approach. PET data were acquired in list-mode and synchronized with respiration. The implemented approach consists first in defining a VOI on the reconstructed motion average image. Gated PET images of the VOI are subsequently reconstructed using only lines of response passing through the selected VOI and are used in combination with a center of gravity or an affine/elastic registration algorithm to derive the transformation maps corresponding to the respiration effects. Those are finally integrated in the reconstruction process to produce a motion free image over the lesion regions. Results: Although the center of gravity or affine algorithm achieved similar performance for individual lesion motion correction, the elastic model, applied either locally or to the whole FOV, led to an overall superior performance. The spatial tumor location was altered by 89% and 81% for the elastic model applied locally or to the whole FOV, respectively (compared to 44% and 39% for the center of gravity and affine models, respectively). This resulted in similar associated overall tumor volume changes of 84% and 80%, respectively (compared to 75% and 71% for the center of gravity and affine models, respectively). The application of the nonrigid

  11. A navigation system for percutaneous needle interventions based on PET/CT images: design, workflow and error analysis of soft tissue and bone punctures.

    PubMed

    Oliveira-Santos, Thiago; Klaeser, Bernd; Weitzel, Thilo; Krause, Thomas; Nolte, Lutz-Peter; Peterhans, Matthias; Weber, Stefan

    2011-01-01

    Percutaneous needle intervention based on PET/CT images is effective, but exposes the patient to unnecessary radiation due to the increased number of CT scans required. Computer assisted intervention can reduce the number of scans, but requires handling, matching and visualization of two different datasets. While one dataset is used for target definition according to metabolism, the other is used for instrument guidance according to anatomical structures. No navigation systems capable of handling such data and performing PET/CT image-based procedures while following clinically approved protocols for oncologic percutaneous interventions are available. The need for such systems is emphasized in scenarios where the target can be located in different types of tissue such as bone and soft tissue. These two tissues require different clinical protocols for puncturing and may therefore give rise to different problems during the navigated intervention. Studies comparing the performance of navigated needle interventions targeting lesions located in these two types of tissue are not often found in the literature. Hence, this paper presents an optical navigation system for percutaneous needle interventions based on PET/CT images. The system provides viewers for guiding the physician to the target with real-time visualization of PET/CT datasets, and is able to handle targets located in both bone and soft tissue. The navigation system and the required clinical workflow were designed taking into consideration clinical protocols and requirements, and the system is thus operable by a single person, even during transition to the sterile phase. Both the system and the workflow were evaluated in an initial set of experiments simulating 41 lesions (23 located in bone tissue and 18 in soft tissue) in swine cadavers. We also measured and decomposed the overall system error into distinct error sources, which allowed for the identification of particularities involved in the process as well

  12. Monitoring of neoadjuvant chemotherapy using multiparametric, ²³Na sodium MR, and multimodality (PET/CT/MRI) imaging in locally advanced breast cancer.

    PubMed

    Jacobs, Michael A; Ouwerkerk, Ronald; Wolff, Antonio C; Gabrielson, Edward; Warzecha, Hind; Jeter, Stacie; Bluemke, David A; Wahl, Richard; Stearns, Vered

    2011-07-01

    We prospectively investigated using advanced magnetic resonance imaging (MRI) and positron emission tomography/computed tomography (PET/CT) to identify radiological biomarkers for treatment response in patients receiving preoperative systemic therapy (PST) for locally advanced breast cancer. Patients with a stage II or III breast cancer receiving PST were selected and underwent positron emission tomography (PET), magnetic resonance imaging (MRI), and breast biopsies at baseline and after the first cycle of PST (days 7-8) during the full course of treatment. PET/CT was acquired after injection of 2-deoxy-2-[18F]-fluoro-D-glucose (¹⁸FDG, 0.22 mCi/kg) and quantified with standardized uptake value assessment (SUV). Diagnostic breast MRI and sodium (²³Na) was acquired at 1.5 T. Total tissue sodium concentration (TSC), response criteria in solid tumors (RECIST), and volumes were quantified. Treatment response was determined by pathological assessment at surgery. Immunohistochemistry values of the proliferative index (Ki-67) were performed on biopsy specimens. Six of nineteen eligible women (43 ± 11 years) who received PST underwent radiological imaging of ¹⁸FDG-PET/CT and MRI for at least two cycles of treatment. Five patients had a pathological partial response (pPR) and one had pathological non-response (pNR). TSC decreased 21% in responders with increases in the non-responder (P = 0.03). Greater reduction in SUV was observed in responders (38%) compared to the non-responder (22%; P = 0.03). MRI volumes decreased after cycle 1 by 42% (responders) and 35% (non-responder; P = 0.11). Proliferation index Ki-67 declined in responders in the first cycle (median = 47%, range = 29-20%), but increased (4%) in the non-responder. Significant decreases in TSC, SUV, and Ki-67 were observed in responders with increases in TSC and Ki-67 in non-responders. Our results demonstrate the feasibility of using multi-modality proton, ²³Na MRI, and PET/CT metrics as radiological

  13. Monitoring of neoadjuvant chemotherapy using multiparametric, 23Na sodium MR, and multimodality (PET/CT/MRI) imaging in locally advanced breast cancer

    PubMed Central

    Ouwerkerk, Ronald; Wolff, Antonio C.; Gabrielson, Edward; Warzecha, Hind; Jeter, Stacie; Bluemke, David A.; Wahl, Richard; Stearns, Vered

    2011-01-01

    We prospectively investigated using advanced magnetic resonance imaging (MRI) and positron emission tomography/computed tomography (PET/CT) to identify radiological biomarkers for treatment response in patients receiving preoperative systemic therapy (PST) for locally advanced breast cancer. Patients with a stage II or III breast cancer receiving PST were selected and underwent positron emission tomography (PET), magnetic resonance imaging (MRI), and breast biopsies at baseline and after the first cycle of PST (days 7–8) during the full course of treatment. PET/CT was acquired after injection of 2-deoxy-2-[18F]-fluoro-D-glucose (18FDG, 0.22 mCi/kg) and quantified with standardized uptake value assessment (SUV). Diagnostic breast MRI and sodium (23Na) was acquired at 1.5 T. Total tissue sodium concentration (TSC), response criteria in solid tumors (RECIST), and volumes were quantified. Treatment response was determined by pathological assessment at surgery. Immunohistochemistry values of the proliferative index (Ki-67) were performed on biopsy specimens. Six of nineteen eligible women (43 ± 11 years) who received PST underwent radiological imaging of 18FDG-PET/CT and MRI for at least two cycles of treatment. Five patients had a pathological partial response (pPR) and one had pathological non-response (pNR). TSC decreased 21% in responders with increases in the non-responder (P = 0.03). Greater reduction in SUV was observed in responders (38%) compared to the non-responder (22%; P = 0.03). MRI volumes decreased after cycle 1 by 42% (responders) and 35% (non-responder; P = 0.11). Proliferation index Ki-67 declined in responders in the first cycle (median = 47%, range = 29–20%), but increased (4%) in the non-responder. Significant decreases in TSC, SUV, and Ki-67 were observed in responders with increases in TSC and Ki-67 in non-responders. Our results demonstrate the feasibility of using multi-modality proton, 23Na MRI, and PET/CT metrics as radiological

  14. PET/MR Versus PET/CT Imaging: Impact on the Clinical Management of Small-Bowel Crohn’s Disease

    PubMed Central

    Pellino, Gianluca; Nicolai, Emanuele; Catalano, Onofrio A.; Campione, Severo; D’Armiento, Francesco P.; Salvatore, Marco; Cuocolo, Alberto

    2016-01-01

    Background and Aims: The aim of this study was to compare the accuracy and clinical impact of hybrid positron emission tomography [PET]/magnetic resonance-enterography [MR-E] and PET/computed tomography-enterography [CT-E] in patients with Crohn’s disease [CD]. Methods: A total of 35 patients with symptomatic small-bowel CD who were scheduled to undergo operation were evaluated before operation by same-day PET/CT-E and PET/MR-E. PET/MR-E was also compared with MR-E alone. Imaging accuracy for detecting pathological sites and discriminating between fibrotic and inflammatory strictures was assessed. Treatment was adjusted according to imaging findings and change in medical/surgical strategy was also evaluated. Results: PET/CT-E, PET/MR-E, and MR-E were equally accurate in detecting CD sites. PET/MR-E was more accurate in assessing extra-luminal disease [p = 0.002], which was associated with higher need for stoma [p = 0.022] and distant localisation [p = 0.002]. When the latter was observed, laparoscopy was started with hand-assisted device, reducing operative time [p = 0.022]. PET/MR-E was also more accurate in detecting a fibrotic component compared with PET/CT-E [p = 0.043] and with MR-E [p = 0.024]. Fibrosis was more frequently classified as inflammation with MR-E compared with PET/MR-E [p = 0.019]. Out of 8 patients with predominantly inflammatory CD who received medical treatment, 6 [75%] remained surgery free. Overall, 29 patients received surgery. At median follow-up of 9 [6–22] months, no recurrences occurred in either the medical or the surgical group. Conclusions: Preoperative PET/MR-E imaging is highly accurate for assessing CD lesions before operation and contributed to clinical management of patients with small-bowel CD more often than PET/CT-E. PMID:26574490

  15. Imaging primary prostate cancer with 11C-Choline PET/CT: relation to tumour stage, Gleason score and biomarkers of biologic aggressiveness

    PubMed Central

    Chen, Ji; Zhao, Yong; Li, Xin; Sun, Peng; Wang, Muwen; Wang, Ridong; Jin, Xunbo

    2012-01-01

    Background As a significant overlap of 11C-Choline standardized uptake value (SUV) between prostate cancer and benign prostate hyperplasia (BPH) tissue, controversy exists regarding the clinical value of 11C-Choline PET/CT scan in primary prostate cancer. In this study, the SUVmax of the prostate lesions and the pelvic muscles were measured and their ratios (SUVmax-P/M ratio) were calculated. Then we evaluated whether the tracer 11C-Choline uptake, quantified as SUVmax-P/M ratio, correlated with tumour stage, Gleason score, and expression levels of several biomarkers of aggressiveness. Methods Twenty-six patients with primary prostate cancer underwent 11C-Choline PET/CT. Tumour specimens from these patients were graded histopathologically, and immunnohistochemistry for Ki-67, CD31, androgen receptor (AR), Her-2/neu, Bcl-2, and PTEN were performed. Results Both SUVmax and SUVmax-P/M ratio showed no significant difference between patients with tumour stage II and III, but significantly elevated in patients with tumour stage IV. SUVmax-P/M ratio was also significantly higher in lesions with Gleason score of 4+3 or higher versus less than or equal to 3+4. SUVmax-P/M ratio was found significantly correlated with expression levels of Ki-67 and CD31. In addition, a higher SUVmax-P/M ratio was demonstrated in Her-2/neu positive subgroup than negative subgroup. At the same time, Gleason score and expression levels of these biomarkers showed no significant association with SUVmax. Conclusions Using the parameter SUVmax-P/M ratio, 11C-Choline PET/CT may be a valuable non-invasive imaging technology in the diagnosis of primary prostate cancer. PMID:23077456

  16. Performance characteristics and relationship of PSA value/kinetics on carbon-11 acetate PET/CT imaging in biochemical relapse of prostate cancer

    PubMed Central

    Almeida, Fabio D; Yen, Chi-Kwan; Scholz, Mark C; Lam, Richard Y; Turner, Jeffrey; Bans, Larry L; Lipson, Robert

    2017-01-01

    An elevated serum prostate-specific antigen (PSA) level alone cannot distinguish between local-regional recurrences and distant metastases after treatment with curative intent. With available salvage treatments, it has become important to localize the site of recurrence. 11C-Acetate PET/CT was performed in patients with rising PSA, with statistical analysis of detection rates, sites/location of detection, PSA kinetics and comparison with other tracers (FDG and Choline). Correlation to biopsy, subsequent imaging and PSA response to focal treatment was also performed. 88% (637) of 721 11C-Acetate PET/CT scans performed were positive. There was a statistically significant difference in PSA values between the positive and negative scans (P < 0.001 for mean difference) with the percentage of positive scans and PSA having a positive correlation. A PSA of 1.09 ng/mL was found to be an optimal cutoff. PSAdT was significantly correlated with a positive scan only when the PSA was < 1.0 ng/mL. For this subgroup, a PSAdT of < 3.8 months appeared significant (P < 0.05) as an optimal cutoff point. 11C-Acetate PET/CT demonstrates a high detection rate for the site of recurrence/metastasis in biochemical relapsed prostate cancer (88% overall detection rate, PPV 90.8%). This analysis suggests an optimal PSA threshold of > 1.09 ng/mL or a PSAdT of < 3.8 months when the PSA is below 1.0 ng/mL as independent predictors of positive findings. PMID:28123863

  17. CT imaging of bone and bone marrow infiltration in malignant melanoma--Challenges and limitations for clinical staging in comparison to 18FDG-PET/CT.

    PubMed

    Bier, Georg; Hoffmann, Vera; Kloth, Christopher; Othman, Ahmed E; Eigentler, Thomas; Garbe, Claus; La Fougère, Christian; Pfannenberg, Christina; Nikolaou, Konstantin; Klumpp, Bernhard

    2016-04-01

    Rationale of this study was the evaluation of the diagnostic value of computed tomography (CT) in the detection of bone marrow infiltration in comparison to PET/CT. Fifty patients (age 61 ± 15.12 years) with metastatic malignant melanoma underwent 18F-FDG-PET/CT, including contrast-enhanced CT. 2 readers evaluated the CT images in consensus for bone and bone marrow lesions focusing on lesion location, type and size. PET/CT was used as reference standard to estimate sensitivity, specificity, negative and positive predictive value. Moreover, the bone marrow density was estimated in the long bones and the sacral bone. Serum hamoglobin, thrombocyte level and S100 protein were correlated with the presence or absence of bone and bone marrow lesions. According to PET/CT as standard of reference, of 594 bone and medullary lesions 495 were considered malignant. Of these 77.8% were medullary, 20.4% lytic, 1% sclerotic and 0.8% mixed lytic/sclerotic. Contrast-enhanced CT yielded a lesion-based sensitivity of 36.8% and a specificity of 87.9% (PPV 93.8%; NPV 21.8%). Patient-based sensitivity and specificity were 78.8% and 82.4%, respectively. Of the missed lesions, most were medullary (95.8%). A disseminated bone marrow involvement (defined as >10 bone marrow lesions or diffuse infiltration of a whole body segment) was described in 11 cases, in 6 cases the disseminated involvement was underestimated or missed on CT. In cases with disseminated bone marrow involvement the bone marrow density was significantly higher in the humerus (p=0.04), but not in the femur or sacral bone (p=0.06). Multivariate analysis revealed no isolated effect of bone metastases on S100 serum and hemoglobin level, but both were significantly altered in patients with disseminated bone marrow involvement (p<0.05). In conclusion, the diagnostic value of computed tomography for the detection of bone marrow metastases in patients with melanoma, is limited. Especially in cases with disseminated bone marrow

  18. The Role of PET/CT Molecular Imaging in the Diagnosis of Recurrence and Surveillance of Patients Treated for Non-Small Cell Lung Cancer

    PubMed Central

    Jiménez-Bonilla, Julio Francisco; Quirce, Remedios; Martínez-Rodríguez, I.; De Arcocha-Torres, María; Carril, José Manuel; Banzo, Ignacio

    2016-01-01

    Non-small cell lung cancer (NSCLC) is the leading cause of cancer mortality worldwide and its prognosis remains poor. Molecular imaging with 18F-FDG PET/CT can metabolically characterize the nature of lesions as benign or malignant, allowing a better staging at the diagnosis of this kind of patient. This advantage can also be applied in the re-staging due to the suspicion of recurrent disease. Many patients have a recurrence of the disease, including surgically treated patients. In the current context, with new personalized oncological treatments, the surveillance for recurrence and its accurate diagnosis are crucial to improve their survival. In this paper, we revise the current knowledge about the clinical and molecular factors related to the recurrent disease. In the context of new, promising, available personalized treatments, the role of molecular imaging with PET/CT and 18F-FDG and non-18F-FDG radiotracers in the follow-up of NSCLC-treated patients is especially attractive and interesting. PMID:27706025

  19. Imaging by ¹⁸F-FDG PET/CT of diffuse large B-cell lymphoma with cellulitis.

    PubMed

    Zhang, Yiqiu; Li, Beilei; Cai, Liang; Shi, Hongcheng; Hou, Jun

    2015-01-01

    Non-Hodgkin's lymphomas (NHL) quite often present in the neck but are seldom accompanied with cellulitis at the first diagnosis of the disease. We report a 56 year old woman with gradually neck swelling, which was initially treated as cellulitis. After examined by ultrasonography, computed tomography and after pathologically assessments, the diagnosis of large B-cell lymphoma was made. This case highlights the usefulness of fluorine-18-fluorodeoxyglucose positron emission tomography (¹⁸F-FDG PET/CT) in staging and assessing treatment response in NHL.

  20. Molecular imaging of late somatostatin receptor-positive metastases of renal cell carcinoma in the pancreas by 68Ga DOTATOC PET/CT: a rare differential diagnosis to multiple primary pancreatic neuroendocrine tumors.

    PubMed

    Peter, Luisa; Sänger, Jörg; Hommann, Merten; Baum, Richard Paul; Kaemmerer, Daniel

    2014-08-01

    Ga somatostatin receptor PET/CT, currently the most sensitive imaging modality for well-differentiated neuroendocrine tumors, is based on the molecular imaging of somatostatin receptors (SSTRs) that are expressed in different tumor entities such as neuroendocrine neoplasms, lymphomas, meningiomas, or renal cell cancer (RCC). Most neuroendocrine neoplasms show a high expression of SSTR subtypes 2A and 5, whereas the overexpression of SSTR2A in RCC is mainly seen in peritumoral vessels. Here we report a case with strongly SSTR-positive pancreatic lesions detected by Ga DOTATOC PET/CT, which histologically turned out to be ultralate metastases of a RCC.

  1. Management of epithelial ovarian cancer from diagnosis to restaging: an overview of the role of imaging techniques with particular regard to the contribution of 18F-FDG PET/CT.

    PubMed

    Musto, Alessandra; Grassetto, Gaia; Marzola, Maria Cristina; Rampin, Lucia; Chondrogiannis, Sotirios; Maffione, Anna Margherita; Colletti, Patrick M; Perkins, Alan C; Fagioli, Giorgio; Rubello, Domenico

    2014-06-01

    Epithelial ovarian carcinoma is a major form of cancer affecting women in the western world. The silent nature of this disease results in late presentation at an advanced stage in many patients. It is therefore important to assess the role of imaging techniques in the management of these patients. This article presents a review of the literature on the role of (18)F-FDG-PET/CT in the different stages of management of epithelial ovarian cancer. Moreover, a comparison with other imaging techniques has been made and the relationship between (18)F-PET/CT and the assay of serum CA-125 levels has been discussed.

  2. Non-invasive breast biopsy method using GD-DTPA contrast enhanced MRI series and F-18-FDG PET/CT dynamic image series

    NASA Astrophysics Data System (ADS)

    Magri, Alphonso William

    This study was undertaken to develop a nonsurgical breast biopsy from Gd-DTPA Contrast Enhanced Magnetic Resonance (CE-MR) images and F-18-FDG PET/CT dynamic image series. A five-step process was developed to accomplish this. (1) Dynamic PET series were nonrigidly registered to the initial frame using a finite element method (FEM) based registration that requires fiducial skin markers to sample the displacement field between image frames. A commercial FEM package (ANSYS) was used for meshing and FEM calculations. Dynamic PET image series registrations were evaluated using similarity measurements SAVD and NCC. (2) Dynamic CE-MR series were nonrigidly registered to the initial frame using two registration methods: a multi-resolution free-form deformation (FFD) registration driven by normalized mutual information, and a FEM-based registration method. Dynamic CE-MR image series registrations were evaluated using similarity measurements, localization measurements, and qualitative comparison of motion artifacts. FFD registration was found to be superior to FEM-based registration. (3) Nonlinear curve fitting was performed for each voxel of the PET/CT volume of activity versus time, based on a realistic two-compartmental Patlak model. Three parameters for this model were fitted; two of them describe the activity levels in the blood and in the cellular compartment, while the third characterizes the washout rate of F-18-FDG from the cellular compartment. (4) Nonlinear curve fitting was performed for each voxel of the MR volume of signal intensity versus time, based on a realistic two-compartment Brix model. Three parameters for this model were fitted: rate of Gd exiting the compartment, representing the extracellular space of a lesion; rate of Gd exiting a blood compartment; and a parameter that characterizes the strength of signal intensities. Curve fitting used for PET/CT and MR series was accomplished by application of the Levenburg-Marquardt nonlinear regression

  3. DICOM for quantitative imaging biomarker development: a standards based approach to sharing clinical data and structured PET/CT analysis results in head and neck cancer research

    PubMed Central

    Clunie, David; Ulrich, Ethan; Bauer, Christian; Wahle, Andreas; Brown, Bartley; Onken, Michael; Riesmeier, Jörg; Pieper, Steve; Kikinis, Ron; Buatti, John; Beichel, Reinhard R.

    2016-01-01

    Background. Imaging biomarkers hold tremendous promise for precision medicine clinical applications. Development of such biomarkers relies heavily on image post-processing tools for automated image quantitation. Their deployment in the context of clinical research necessitates interoperability with the clinical systems. Comparison with the established outcomes and evaluation tasks motivate integration of the clinical and imaging data, and the use of standardized approaches to support annotation and sharing of the analysis results and semantics. We developed the methodology and tools to support these tasks in Positron Emission Tomography and Computed Tomography (PET/CT) quantitative imaging (QI) biomarker development applied to head and neck cancer (HNC) treatment response assessment, using the Digital Imaging and Communications in Medicine (DICOM®) international standard and free open-source software. Methods. Quantitative analysis of PET/CT imaging data collected on patients undergoing treatment for HNC was conducted. Processing steps included Standardized Uptake Value (SUV) normalization of the images, segmentation of the tumor using manual and semi-automatic approaches, automatic segmentation of the reference regions, and extraction of the volumetric segmentation-based measurements. Suitable components of the DICOM standard were identified to model the various types of data produced by the analysis. A developer toolkit of conversion routines and an Application Programming Interface (API) were contributed and applied to create a standards-based representation of the data. Results. DICOM Real World Value Mapping, Segmentation and Structured Reporting objects were utilized for standards-compliant representation of the PET/CT QI analysis results and relevant clinical data. A number of correction proposals to the standard were developed. The open-source DICOM toolkit (DCMTK) was improved to simplify the task of DICOM encoding by introducing new API abstractions

  4. DICOM for quantitative imaging biomarker development: a standards based approach to sharing clinical data and structured PET/CT analysis results in head and neck cancer research.

    PubMed

    Fedorov, Andriy; Clunie, David; Ulrich, Ethan; Bauer, Christian; Wahle, Andreas; Brown, Bartley; Onken, Michael; Riesmeier, Jörg; Pieper, Steve; Kikinis, Ron; Buatti, John; Beichel, Reinhard R

    2016-01-01

    Background. Imaging biomarkers hold tremendous promise for precision medicine clinical applications. Development of such biomarkers relies heavily on image post-processing tools for automated image quantitation. Their deployment in the context of clinical research necessitates interoperability with the clinical systems. Comparison with the established outcomes and evaluation tasks motivate integration of the clinical and imaging data, and the use of standardized approaches to support annotation and sharing of the analysis results and semantics. We developed the methodology and tools to support these tasks in Positron Emission Tomography and Computed Tomography (PET/CT) quantitative imaging (QI) biomarker development applied to head and neck cancer (HNC) treatment response assessment, using the Digital Imaging and Communications in Medicine (DICOM(®)) international standard and free open-source software. Methods. Quantitative analysis of PET/CT imaging data collected on patients undergoing treatment for HNC was conducted. Processing steps included Standardized Uptake Value (SUV) normalization of the images, segmentation of the tumor using manual and semi-automatic approaches, automatic segmentation of the reference regions, and extraction of the volumetric segmentation-based measurements. Suitable components of the DICOM standard were identified to model the various types of data produced by the analysis. A developer toolkit of conversion routines and an Application Programming Interface (API) were contributed and applied to create a standards-based representation of the data. Results. DICOM Real World Value Mapping, Segmentation and Structured Reporting objects were utilized for standards-compliant representation of the PET/CT QI analysis results and relevant clinical data. A number of correction proposals to the standard were developed. The open-source DICOM toolkit (DCMTK) was improved to simplify the task of DICOM encoding by introducing new API abstractions

  5. Evaluation of the combined effects of target size, respiratory motion and background activity on 3D and 4D PET/CT images

    NASA Astrophysics Data System (ADS)

    Park, Sang-June; Ionascu, Dan; Killoran, Joseph; Mamede, Marcelo; Gerbaudo, Victor H.; Chin, Lee; Berbeco, Ross

    2008-07-01

    Gated (4D) PET/CT has the potential to greatly improve the accuracy of radiotherapy at treatment sites where internal organ motion is significant. However, the best methodology for applying 4D-PET/CT to target definition is not currently well established. With the goal of better understanding how to best apply 4D information to radiotherapy, initial studies were performed to investigate the effect of target size, respiratory motion and target-to-background activity concentration ratio (TBR) on 3D (ungated) and 4D PET images. Using a PET/CT scanner with 4D or gating capability, a full 3D-PET scan corrected with a 3D attenuation map from 3D-CT scan and a respiratory gated (4D) PET scan corrected with corresponding attenuation maps from 4D-CT were performed by imaging spherical targets (0.5-26.5 mL) filled with 18F-FDG in a dynamic thorax phantom and NEMA IEC body phantom at different TBRs (infinite, 8 and 4). To simulate respiratory motion, the phantoms were driven sinusoidally in the superior-inferior direction with amplitudes of 0, 1 and 2 cm and a period of 4.5 s. Recovery coefficients were determined on PET images. In addition, gating methods using different numbers of gating bins (1-20 bins) were evaluated with image noise and temporal resolution. For evaluation, volume recovery coefficient, signal-to-noise ratio and contrast-to-noise ratio were calculated as a function of the number of gating bins. Moreover, the optimum thresholds which give accurate moving target volumes were obtained for 3D and 4D images. The partial volume effect and signal loss in the 3D-PET images due to the limited PET resolution and the respiratory motion, respectively were measured. The results show that signal loss depends on both the amplitude and pattern of respiratory motion. However, the 4D-PET successfully recovers most of the loss induced by the respiratory motion. The 5-bin gating method gives the best temporal resolution with acceptable image noise. The results based on the 4D

  6. SU-D-9A-04: Brain PET/CT Imaging On a Scanner with a Large Axial Field-Of-View

    SciTech Connect

    Park, M; Gerbaudo, V; Hamberg, L; Seaver, K; Kijewski, M

    2014-06-01

    Purpose: Large axial field-of-view (FOV) PET/CT scanners are valued for high sensitivity. Brain PET image quality may depend on the head position within the FOV. We investigated the precision of activity estimation for brain PET imaging when the brain was positioned at the end (END) and in the middle (CEN) of the FOV. The additional CT dose for the CEN position was recorded. Methods: An image quality (Jaszczak) phantom and a striatal phantom were filled with F-18 and positioned in END and CEN locations. For each phantom and each location, we acquired a ∼1-hr listmode PET, rebinned the data into 10 frames with equal number of coincidence events, and reconstructed each frame using an iterative algorithm. For the striatal phantom, END and CEN were compared by drawing on each image three regions of interest (ROI) in axially separated uniform areas. The standard deviation of the activity estimation within each ROI was averaged over the 10 images. The coefficient of variation (CV) for activity estimation was calculated at each position. Image quality was assessed by inspecting the resolution bar pattern in the Jaszczak phantom at two different head positions. Results: The CV was the lowest for ROIs near the center of the FOV. For slices near the end, not only was the CV highest, but also the resolution pattern was degraded. CTDIvol summarized in the dose report indicated that the CT dose was ∼ 10% higher for CEN as compared to END position. Conclusion: Positioning the brain in the middle of the FOV in a large FOV PET/CT scanner allows more precise measurement of tracer uptake and better image quality at the cost of increased CT dose. For the end location longer scan times may minimize image quality degradation without any additional CT dose.

  7. A novel 3D graph cut based co-segmentation of lung tumor on PET-CT images with Gaussian mixture models

    NASA Astrophysics Data System (ADS)

    Yu, Kai; Chen, Xinjian; Shi, Fei; Zhu, Weifang; Zhang, Bin; Xiang, Dehui

    2016-03-01

    Positron Emission Tomography (PET) and Computed Tomography (CT) have been widely used in clinical practice for radiation therapy. Most existing methods only used one image modality, either PET or CT, which suffers from the low spatial resolution in PET or low contrast in CT. In this paper, a novel 3D graph cut method is proposed, which integrated Gaussian Mixture Models (GMMs) into the graph cut method. We also employed the random walk method as an initialization step to provide object seeds for the improvement of the graph cut based segmentation on PET and CT images. The constructed graph consists of two sub-graphs and a special link between the sub-graphs which penalize the difference segmentation between the two modalities. Finally, the segmentation problem is solved by the max-flow/min-cut method. The proposed method was tested on 20 patients' PET-CT images, and the experimental results demonstrated the accuracy and efficiency of the proposed algorithm.

  8. 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.

  9. SU-E-I-100: Heterogeneity Studying for Primary and Lymphoma Tumors by Using Multi-Scale Image Texture Analysis with PET-CT Images

    SciTech Connect

    Li, Dengwang; Wang, Qinfen; Li, H; Chen, J

    2014-06-01

    Purpose: The purpose of this research is studying tumor heterogeneity of the primary and lymphoma by using multi-scale texture analysis with PET-CT images, where the tumor heterogeneity is expressed by texture features. Methods: Datasets were collected from 12 lung cancer patients, and both of primary and lymphoma tumors were detected with all these patients. All patients underwent whole-body 18F-FDG PET/CT scan before treatment.The regions of interest (ROI) of primary and lymphoma tumor were contoured by experienced clinical doctors. Then the ROI of primary and lymphoma tumor is extracted automatically by using Matlab software. According to the geometry size of contour structure, the images of tumor are decomposed by multi-scale method.Wavelet transform was performed on ROI structures within images by L layers sampling, and then wavelet sub-bands which have the same size of the original image are obtained. The number of sub-bands is 3L+1.The gray level co-occurrence matrix (GLCM) is calculated within different sub-bands, thenenergy, inertia, correlation and gray in-homogeneity were extracted from GLCM.Finally, heterogeneity statistical analysis was studied for primary and lymphoma tumor using the texture features. Results: Energy, inertia, correlation and gray in-homogeneity are calculated with our experiments for heterogeneity statistical analysis.Energy for primary and lymphomatumor is equal with the same patient, while gray in-homogeneity and inertia of primaryare 2.59595±0.00855, 0.6439±0.0007 respectively. Gray in-homogeneity and inertia of lymphoma are 2.60115±0.00635, 0.64435±0.00055 respectively. The experiments showed that the volume of lymphoma is smaller than primary tumor, but thegray in-homogeneity and inertia were higher than primary tumor with the same patient, and the correlation with lymphoma tumors is zero, while the correlation with primary tumor isslightly strong. Conclusion: This studying showed that there were effective heterogeneity

  10. Site specific discrete PEGylation of (124)I-labeled mCC49 Fab' fragments improves tumor MicroPET/CT imaging in mice.

    PubMed

    Ding, Haiming; Carlton, Michelle M; Povoski, Stephen P; Milum, Keisha; Kumar, Krishan; Kothandaraman, Shankaran; Hinkle, George H; Colcher, David; Brody, Rich; Davis, Paul D; Pokora, Alex; Phelps, Mitchell; Martin, Edward W; Tweedle, Michael F

    2013-11-20

    The tumor-associated glycoprotein-72 (TAG-72) antigen is highly overexpressed in various human adenocarcinomas and anti-TAG-72 monoclonal antibodies, and fragments are therefore useful as pharmaceutical targeting vectors. In this study, we investigated the effects of site-specific PEGylation with MW 2-4 kDa discrete, branched PEGylation reagents on mCC49 Fab' (MW 50 kDa) via in vitro TAG72 binding, and in vivo blood clearance kinetics, biodistribution, and mouse tumor microPET/CT imaging. mCC49Fab' (Fab'-NEM) was conjugated at a hinge region cysteine with maleimide-dPEG 12-(dPEG24COOH)3 acid (Mal-dPEG-A), maleimide-dPEG12-(dPEG12COOH)3 acid (Mal-dPEG-B), or maleimide-dPEG12-(m-dPEG24)3 (Mal-dPEG-C), and then radiolabeled with iodine-124 ((124)I) in vitro radioligand binding assays and in vivo studies used TAG-72 expressing LS174T human colon carcinoma cells and xenograft mouse tumors. Conjugation of mCC49Fab' with Mal-dPEG-A (Fab'-A) reduced the binding affinity of the non PEGylated Fab' by 30%; however, in vivo, Fab'-A significantly lengthened the blood retention vs Fab'-NEM (47.5 vs 28.1%/ID at 1 h, 25.1 vs 8.4%/ID at 5 h, p < 0.01), showed excellent tumor to background, better microPET/CT images due to higher tumor accumulation, and increased tumor concentration in excised tissues at 72 h by 130% (5.09 ± 0.83 vs 3.83 ± 1.50%ID/g, p < 0.05). Despite the strong similarity of the three PEGylation reagents, PEGylation with Mal-dPEG-B or -C reduced the in vitro binding affinity of Fab'-NEM by 70%, blood retention, microPET/CT imaging tumor signal intensity, and residual 72 h tumor concentration by 49% (3.83 ± 1.50 vs 1.97 ± 0.29%ID/g, p < 0.05) and 63% (3.83 ± 1.50 vs 1.42 ± 0.35%ID/g, p < 0.05), respectively. We conclude that remarkably subtle changes in the structure of the PEGylation reagent can create significantly altered biologic behavior. Further study is warranted of conjugates of the triple branched, negatively charged Mal-dPEG-A.

  11. Site Specific Discrete PEGylation of 124I-Labeled mCC49 Fab′ Fragments Improves Tumor MicroPET/CT Imaging in Mice

    PubMed Central

    Ding, Haiming; Carlton, Michelle M.; Povoski, Stephen P.; Milum, Keisha; Kumar, Krishan; Kothandaraman, Shankaran; Hinkle, George H.; Colcher, David; Brody, Rich; Davis, Paul D.; Pokora, Alex; Phelps, Mitchell; Martin, Edward W.; Tweedle, Michael F.

    2014-01-01

    The tumor-associated glycoprotein-72 (TAG-72) antigen is highly overexpressed in various human adenocarcinomas and anti-TAG-72 monoclonal antibodies, and fragments are therefore useful as pharmaceutical targeting vectors. In this study, we investigated the effects of site-specific PEGylation with MW 2–4 kDa discrete, branched PEGylation reagents on mCC49 Fab′ (MW 50 kDa) via in vitro TAG72 binding, and in vivo blood clearance kinetics, biodistribution, and mouse tumor microPET/CT imaging. mCC49Fab′ (Fab′-NEM) was conjugated at a hinge region cysteine with maleimide-dPEG12-(dPEG24COOH)3 acid (Mal-dPEG-A), maleimide-dPEG12-(dPEG12COOH)3 acid (Mal-dPEG-B), or maleimide-dPEG12-(m-dPEG24)3 (Mal-dPEG-C), and then radiolabeled with iodine-124 (124I) in vitro radioligand binding assays and in vivo studies used TAG-72 expressing LS174T human colon carcinoma cells and xenograft mouse tumors. Conjugation of mCC49Fab′ with Mal-dPEG-A (Fab′-A) reduced the binding affinity of the non PEGylated Fab′ by 30%; however, in vivo, Fab′-A significantly lengthened the blood retention vs Fab′-NEM (47.5 vs 28.1%/ID at 1 h, 25.1 vs 8.4%/ID at 5 h, p < 0.01), showed excellent tumor to background, better microPET/CT images due to higher tumor accumulation, and increased tumor concentration in excised tissues at 72 h by 130% (5.09 ± 0.83 vs 3.83 ± 1.50%ID/g, p < 0.05). Despite the strong similarity of the three PEGylation reagents, PEGylation with Mal-dPEG-B or -C reduced the in vitro binding affinity of Fab′-NEM by 70%, blood retention, microPET/CT imaging tumor signal intensity, and residual 72 h tumor concentration by 49% (3.83 ± 1.50 vs 1.97 ± 0.29%ID/g, p < 0.05) and 63% (3.83 ± 1.50 vs 1.42 ± 0.35%ID/g, p < 0.05), respectively. We conclude that remarkably subtle changes in the structure of the PEGylation reagent can create significantly altered biologic behavior. Further study is warranted of conjugates of the triple branched, negatively charged Mal-dPEG-A. PMID

  12. Bing-Neel Syndrome Case Report: A Previously Undocumented IgG Variant with MRI, PET/CT, and PET/MRI Imaging.

    PubMed

    Halperin, Daniel; Hallam, Simon; Haroon, Athar; Butler, Tom; Agrawal, Samir

    2016-01-01

    Waldenstrom's macroglobulinaemia is the most commonly reported subtype of lymphoplasmacytic lymphoma (LPL); it is characterised by IgM secretion. Neurological complications are common usually as a result of hyperviscosity. In rare cases, cells can infiltrate the central nervous system; this is known as Bing-Neel syndrome. We report the case of a 57-year-old male with lymphoplasmacytic lymphoma of the IgG-subtype with neurological symptoms and the consequent finding of lymphoplasmacytoid cells in his cerebrospinal fluid as well as deposits on MRI and PET-CT imaging. This is the first report of Bing-Neel syndrome in IgG-subtype LPL. We discuss the biological and radiological markers of his disease, including PET imaging, which has been minimal in this area to date.

  13. A pilot study of the prognostic significance of metabolic tumor size measurements in PET/CT imaging of lymphomas

    NASA Astrophysics Data System (ADS)

    Kallergi, Maria; Botsivali, Maria; Politis, Nikolaos; Menychtas, Dimitrios; Georgakopoulos, Alexandros; Chatziioannou, Sofia

    2015-03-01

    This study explores changes in metabolic tumor volume, metabolic tumor diameter, and maximum standardized uptake value (SUVmax), for earlier and more accurate identification of lymphomas' response to treatment using 18F- FDG PET/CT. Pre- and post-treatment PET/CT studies of 20 patients with Hodgkin disease (HL) and 7 patients with non- Hodgkin lymphoma (NHL) were retrospectively selected for this study. The diameter and volume of the metabolic tumor was determined by an in-house developed adaptive local thresholding technique based on a 50% threshold of the maximum pixel value within a region. Statistical analysis aimed at exploring associations between metabolic size measurements and SUVmax and the ability of the three biomarkers to predict the patients' response to treatment as defined by the four classes in the European Organization for Research and Treatment of Cancer (EORTC) guidelines. Results indicated moderate correlations between % change in metabolic tumor volume and % change in metabolic tumor maximum diameter (R=0.51) and between % change in maximum diameter and % change in SUVmax (R=0.52). The correlation between % change in tumor volume and % change in SUVmax was weak (R=0.24). The % change in metabolic tumor size, either volume or diameter, was a "very strong" predictor of response to treatment (R=0.89), stronger than SUVmax (R=0.63). In conclusion, metabolic tumor volume could have important prognostic value, possibly higher than maximum metabolic diameter or SUVmax that are currently the standard of practice. Volume measurements, however, should be based on robust and standardized segmentation methodologies to avoid variability. In addition, SUV-peak or lean body mass corrected SUV-peak may be a better PET biomarker than SUVmax when SUV-volume combinations are considered.

  14. How we read FCH-PET/CT for prostate cancer.

    PubMed

    Beauregard, Jean-Mathieu; Beaulieu, Alexis

    2016-12-06

    Over the last decade, (18)F-fluorocholine positron emission tomography/computed tomography (FCH-PET/CT) has gained in popularity for the staging and restaging of patients with prostate cancer (PCa). However, despite abundant literature on the topic, there is a lack of publications on how to actually interpret FCH-PET/CT in a clinical setting. Here we propose a practical, TNM-oriented approach to read FCH-PET/CT, with notes on procedure technique, image display, review sequence and report structure. The purpose of this article is to provide guidance to radiologists, nuclear medicine physicians and residents who are new to FCH-PET/CT, as well as to propose an alternate approach to more experienced physicians.

  15. Synthesis, 68Ga-Radiolabeling, and Preliminary In Vivo Assessment of a Depsipeptide-Derived Compound as a Potential PET/CT Infection Imaging Agent

    PubMed Central

    Mokaleng, Botshelo B.; Ebenhan, Thomas; Ramesh, Suhas; Govender, Thavendran; Kruger, Hendrik G.; Hazari, Puja P.; Mishra, Anil K.; Marjanovic-Painter, Biljana; Zeevaart, Jan R.; Sathekge, Mike M.

    2015-01-01

    Noninvasive imaging is a powerful tool for early diagnosis and monitoring of various disease processes, such as infections. An alarming shortage of infection-selective radiopharmaceuticals exists for overcoming the diagnostic limitations with unspecific tracers such as 67/68Ga-citrate or 18F-FDG. We report here TBIA101, an antimicrobial peptide derivative that was conjugated to DOTA and radiolabeled with 68Ga for a subsequent in vitro assessment and in vivo infection imaging using Escherichia coli-bearing mice by targeting bacterial lipopolysaccharides with PET/CT. Following DOTA-conjugation, the compound was verified for its cytotoxic and bacterial binding behaviour and compound stability, followed by 68Gallium-radiolabeling. µPET/CT using 68Ga-DOTA-TBIA101 was employed to detect muscular E. coli-infection in BALB/c mice, as warranted by the in vitro results. 68Ga-DOTA-TBIA101-PET detected E. coli-infected muscle tissue (SUV = 1.3–2.4) > noninfected thighs (P = 0.322) > forearm muscles (P = 0.092) > background (P = 0.021) in the same animal. Normalization of the infected thigh muscle to reference tissue showed a ratio of 3.0 ± 0.8 and a ratio of 2.3 ± 0.6 compared to the identical healthy tissue. The majority of the activity was cleared by renal excretion. The latter findings warrant further preclinical imaging studies of greater depth, as the DOTA-conjugation did not compromise the TBIA101's capacity as targeting vector. PMID:25699267

  16. MicroPET/CT Imaging of an Orthotopic Model of Human Glioblastoma Multiforme and Evaluation of Pulsed Low-Dose Irradiation

    SciTech Connect

    Park, Sean S.; Chunta, John L.; Robertson, John M.; Martinez, Alvaro A.; Oliver Wong, Ching-Yee; Amin, Mitual; Wilson, George D.; Marples, Brian

    2011-07-01

    Purpose: Glioblastoma multiforme (GBM) is an aggressive tumor that typically causes death due to local progression. To assess a novel low-dose radiotherapy regimen for treating GBM, we developed an orthotopic murine model of human GBM and evaluated in vivo treatment efficacy using micro-positron-emission tomography/computed tomography (microPET/CT) tumor imaging. Methods: Orthotopic GBM xenografts were established in nude mice and treated with standard 2-Gy fractionation or 10 0.2-Gy pulses with 3-min interpulse intervals, for 7 consecutive days, for a total dose of 14 Gy. Tumor growth was quantified weekly using the Flex Triumph (GE Healthcare/Gamma Medica-Ideas, Waukesha, WI) combined PET-single-photon emission CT (SPECT)-CT imaging system and necropsy histopathology. Normal tissue damage was assessed by counting dead neural cells in tissue sections from irradiated fields. Results: Tumor engraftment efficiency for U87MG cells was 86%. Implanting 0.5 x 10{sup 6} cells produced a 50- to 70-mm{sup 3} tumor in 10 to 14 days. A significant correlation was seen between CT-derived tumor volume and histopathology-measured volume (p = 0.018). The low-dose 0.2-Gy pulsed regimen produced a significantly longer tumor growth delay than standard 2-Gy fractionation (p = 0.045). Less normal neuronal cell death was observed after the pulsed delivery method (p = 0.004). Conclusion: This study successfully demonstrated the feasibility of in vivo brain tumor imaging and longitudinal assessment of tumor growth and treatment response with microPET/CT. Pulsed radiation treatment was more efficacious than the standard fractionated treatment and was associated with less normal tissue damage.

  17. Recommendations of the Spanish Societies of Radiation Oncology (SEOR), Nuclear Medicine & Molecular Imaging (SEMNiM), and Medical Physics (SEFM) on 18F-FDG PET-CT for radiotherapy treatment planning

    PubMed Central

    Caballero Perea, Begoña; Villegas, Antonio Cabrera; Rodríguez, José Miguel Delgado; Velloso, María José García; Vicente, Ana María García; Cabrerizo, Carlos Huerga; López, Rosa Morera; Romasanta, Luis Alberto Pérez; Beltrán, Moisés Sáez

    2012-01-01

    Positron emission tomography (PET) with 18F-fluorodeoxyglucose (FDG) is a valuable tool for diagnosing and staging malignant lesions. The fusion of PET and computed tomography (CT) yields images that contain both metabolic and morphological information, which, taken together, have improved the diagnostic precision of PET in oncology. The main imaging modality for planning radiotherapy treatment is CT. However, PET-CT is an emerging modality for use in planning treatments because it allows for more accurate treatment volume definition. The use of PET-CT for treatment planning is highly complex, and protocols and standards for its use are still being developed. It seems probable that PET-CT will eventually replace current CT-based planning methods, but this will require a full understanding of the relevant technical aspects of PET-CT planning. The aim of the present document is to review these technical aspects and to provide recommendations for clinical use of this imaging modality in the radiotherapy planning process. PMID:24377032

  18. Recommendations of the Spanish Societies of Radiation Oncology (SEOR), Nuclear Medicine & Molecular Imaging (SEMNiM), and Medical Physics (SEFM) on (18)F-FDG PET-CT for radiotherapy treatment planning.

    PubMed

    Caballero Perea, Begoña; Villegas, Antonio Cabrera; Rodríguez, José Miguel Delgado; Velloso, María José García; Vicente, Ana María García; Cabrerizo, Carlos Huerga; López, Rosa Morera; Romasanta, Luis Alberto Pérez; Beltrán, Moisés Sáez

    2012-01-01

    Positron emission tomography (PET) with (18)F-fluorodeoxyglucose (FDG) is a valuable tool for diagnosing and staging malignant lesions. The fusion of PET and computed tomography (CT) yields images that contain both metabolic and morphological information, which, taken together, have improved the diagnostic precision of PET in oncology. The main imaging modality for planning radiotherapy treatment is CT. However, PET-CT is an emerging modality for use in planning treatments because it allows for more accurate treatment volume definition. The use of PET-CT for treatment planning is highly complex, and protocols and standards for its use are still being developed. It seems probable that PET-CT will eventually replace current CT-based planning methods, but this will require a full understanding of the relevant technical aspects of PET-CT planning. The aim of the present document is to review these technical aspects and to provide recommendations for clinical use of this imaging modality in the radiotherapy planning process.

  19. Specificity of 68Ga-PSMA PET/CT for Prostate Cancer - Myths and Reality

    PubMed Central

    Sasikumar, Arun

    2017-01-01

    68Ga-PSMA ligand PET/CT for imaging prostate cancer is a novel imaging technique, which is rapidly gaining popularity. Sufficient evidence has been accumulated in literature regarding the usefulness of 68Ga-PSMA PET/CT in prostate cancer. Recently literature regarding the localization of 68Ga-PSMA PET/CT imaging in non-prostatic malignancies is also published, thus questioning the specificity of the tracer with regards to prostate cancer. This commentary tries to address the issue of specificity of 68Ga-PSMA PET/CT and its relevance in imaging prostate cancer. PMID:28242976

  20. Specificity of (68)Ga-PSMA PET/CT for Prostate Cancer - Myths and Reality.

    PubMed

    Sasikumar, Arun

    2017-01-01

    68Ga-PSMA ligand PET/CT for imaging prostate cancer is a novel imaging technique, which is rapidly gaining popularity. Sufficient evidence has been accumulated in literature regarding the usefulness of (68)Ga-PSMA PET/CT in prostate cancer. Recently literature regarding the localization of (68)Ga-PSMA PET/CT imaging in non-prostatic malignancies is also published, thus questioning the specificity of the tracer with regards to prostate cancer. This commentary tries to address the issue of specificity of 68Ga-PSMA PET/CT and its relevance in imaging prostate cancer.

  1. [68Ga]Pentixafor-PET/CT for imaging of chemokine receptor CXCR4 expression in multiple myeloma - Comparison to [18F]FDG and laboratory values

    PubMed Central

    Lapa, Constantin; Schreder, Martin; Schirbel, Andreas; Samnick, Samuel; Kortüm, Klaus Martin; Herrmann, Ken; Kropf, Saskia; Einsele, Herrmann; Buck, Andreas K.; Wester, Hans-Jürgen; Knop, Stefan; Lückerath, Katharina

    2017-01-01

    Chemokine (C-X-C motif) receptor 4 (CXCR4) is a key factor for tumor growth and metastasis in several types of human cancer including multiple myeloma (MM). Proof-of-concept of CXCR4-directed radionuclide therapy in MM has recently been reported. This study assessed the diagnostic performance of the CXCR4-directed radiotracer [68Ga]Pentixafor in MM and a potential role for stratifying patients to CXCR4-directed therapies. Thirty-five patients with MM underwent [68Ga]Pentixafor-PET/CT for evaluation of eligibility for endoradiotherapy. In 19/35 cases, [18F]FDG-PET/CT for correlation was available. Scans were compared on a patient and on a lesion basis. Tracer uptake was correlated with standard clinical parameters of disease activity. [68Ga]Pentixafor-PET detected CXCR4-positive disease in 23/35 subjects (66%). CXCR4-positivity at PET was independent from myeloma subtypes, cytogenetics or any serological parameters and turned out as a negative prognostic factor. In the 19 patients in whom a comparison to [18F]FDG was available, [68Ga]Pentixafor-PET detected more lesions in 4/19 (21%) subjects, [18F]FDG proved superior in 7/19 (37%). In the remaining 8/19 (42%) patients, both tracers detected an equal number of lesions. [18F]FDG-PET positivity correlated with [68Ga]Pentixafor-PET positivity (p=0.018). [68Ga]Pentixafor-PET provides further evidence that CXCR4 expression frequently occurs in advanced multiple myeloma, representing a negative prognostic factor and a potential target for myeloma specific treatment. However, selecting patients for CXCR4 directed therapies and prognostic stratification seem to be more relevant clinical applications for this novel imaging modality, rather than diagnostic imaging of myeloma. PMID:28042328

  2. 18F-Sodium Fluoride PET-CT Hybrid Imaging of the Lumbar Facet Joints: Tracer Uptake and Degree of Correlation to CT-graded Arthropathy

    PubMed Central

    Mabray, Marc C.; Brus-Ramer, Marcel; Behr, Spencer C.; Pampaloni, Miguel H.; Majumdar, Sharmila; Dillon, William P.; Talbott, Jason F.

    2016-01-01

    We aim to evaluate 18F-NaF uptake by facet joints with hybrid PET-CT technique. Specifically, we evaluate NaF uptake in the facet joints of the lower lumbar spine, and correlate with the morphologic grade of facet arthropathy on CT. 30 consecutive patients who underwent standard vertex to toes NaF PET-CT for re-staging of primary neoplastic disease without measurable or documented bony metastases were identified. Maximum (SUVmax) and average (SUVavg) standardized uptake values were calculated for each L3-4, L4-5, and L5-S1 facet joint (n = 180) and normalized to average uptake in the non-diseased femur. A Pathria grade (0-3) was assigned to each facet based upon the CT morphology. Spearman's rank correlation was performed for normalized SUVmax and SUVavg with Pathria grade. ANOVA was performed with Tukey-Kramer pairwise tests to evaluate differences in uptake between Pathria groups. Facet normalized SUVmax (r = 0.31, P < 0.001) and SUVavg (r = 0.28, P < 0.001) demonstrated a mild positive correlation with CT Pathria grade. There was a wide range of uptake values within each Pathria grade subgroup with statistically significant differences in uptake only between Pathria grade 3 as compared to grades 0, 1, and 2. In conclusion, NaF uptake and morphologic changes of the facet joint on CT are weakly correlated. Physiologic information provided by NaF uptake is often discrepant with structural findings on CT suggesting NaF PET may supplement conventional structural imaging for identification of pain generating facet joints. Prospective investigation into the relationship of facet joint NaF uptake with pain and response to pain interventions is warranted. PMID:27134557

  3. SU-E-T-189: First Experimental Verification of the Accuracy of Absolute Dose Reconstruction From PET-CT Imaging of Yttrium 90 Microspheres

    SciTech Connect

    Veltchev, I; Fourkal, E; Doss, M; Ma, C; Meyer, J; Yu, M; Horwitz, E

    2014-06-01

    Purpose: In the past few years there have been numerous proposals for 3D dose reconstruction from the PET-CT imaging of patients undergoing radioembolization treatment of the liver with yttrium-90 microspheres. One of the most promising techniques uses convolution of the measured PET activity distribution with a pre-calculated Monte Carlo dose deposition kernel. The goal of the present study is to experimentally verify the accuracy of this method and to analyze the significance of various error sources. Methods: Optically stimulated luminescence detectors (OSLD) were used (NanoDot, Landauer) in this experiment. Two detectors were mounted on the central axis of a cylinder filled with water solution of yttrium-90 chloride. The total initial activity was 90mCi. The cylinder was inserted in a larger water phantom and scanned on a Siemens Biograph 16 Truepoint PET-CT scanner. Scans were performed daily over a period of 20 days to build a calibration curve for the measured absolute activity spanning 7 yttrium-90 half-lives. The OSLDs were mounted in the phantom for a predetermined period of time in order to record 2Gy dose. The measured dose was then compared to the dose reconstructed from the activity density at the location of each dosimeter. Results: Thorough error analysis of the dose reconstruction algorithm takes into account the uncertainties in the absolute PET activity, branching ratios, and nonlinearity of the calibration curve. The measured dose for 105-minute exposure on day 10 of the experiment was 219(11)cGy, while the reconstructed dose at the location of the detector was 215(47)cGy. Conclusion: We present the first experimental verification of the accuracy of the convolution algorithm for absolute dose reconstruction of yttrium-90 microspheres. The excellent agreement between the measured and calculated point doses will encourage the broad clinical adoption of the convolution-based dose reconstruction algorithm, making future quantitative dose

  4. Dual-modality PET/CT instrumentation-today and tomorrow.

    PubMed

    Lonsdale, Markus Nowak; Beyer, Thomas

    2010-03-01

    Positron emission tomography (PET) has proven to be a clinically valuable imaging modality, particularly for oncology staging and therapy follow-up. The introduction of combined PET/CT imaging has helped address challenging imaging situations when anatomical information on PET-only was inadequate for accurate lesion localization. After a decade of PET/CT these combined systems have matured technically. Today, whole-body oncology staging is available with PET/CT in 15 min, or less. This review details recent developments in combined PET/CT instrumentation and points to implications for major applications in clinical oncology.

  5. Effect of {sup 18}F-FDG PET/CT Imaging in Patients With Clinical Stage II and III Breast Cancer

    SciTech Connect

    Groheux, David Moretti, Jean-Luc; Baillet, Georges; Espie, Marc; Giacchetti, Sylvie; Hindie, Elif; Hennequin, Christophe; Vilcoq, Jacques-Robert; Cuvier, Caroline; Toubert, Marie-Elisabeth; Filmont, Jean-Emmanuel; Sarandi, Farid; Misset, Jean-Louis

    2008-07-01

    Purpose: To investigate the potential effect of using {sup 18}F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) in the initial assessment of patients with clinical Stage II or III breast cancer. Methods and Materials: During 14 consecutive months, 39 patients (40 tumors) who presented with Stage II or III breast cancer on the basis of a routine extension assessment were prospectively included in this study. PET/CT was performed in addition to the initial assessment. Results: In 3 cases, PET/CT showed extra-axillary lymph node involvement that had not been demonstrated with conventional techniques. Two of these patients had hypermetabolic lymph nodes in the subpectoral and infraclavicular regions, and the third had a hypermetabolic internal mammary node. PET/CT showed distant uptake in 4 women. Of these 4 women, 1 had pleural involvement and 3 had bone metastasis. Overall, of the 39 women, the PET/CT results modified the initial stage in 7 (18%). The modified staging altered the treatment plan for 5 patients (13%). It led to radiotherapy in 4 patients (bone metastasis, pleural lesion, subpectoral lymph nodes, and internal mammary nodes) and excision of, and radiotherapy to, the infraclavicular lymph nodes in 1 patient. Conclusions: PET/CT can provide information on extra-axillary lymph node involvement and can uncover occult distant metastases in a significant percentage of patients. Therefore, initial PET/CT could enable better treatment planning for patients with Stage II and III breast cancer.

  6. [PET/CT in breast cancer: an update].

    PubMed

    Groheux, D; Moretti, J-L; Giacchetti, S; Hindié, E; Teyton, P; Cuvier, C; Bousquet, G; Misset, J-L; Boin, C; Espié, M

    2009-11-01

    The authors discuss the various roles of 18F-FDG PET/CT in the management of breast cancer. Roles of new tracers such as F-18 fluoro-L-thymidine (a marker of cell proliferation), 18-fluoro-17-B-estradiol (marker of estrogen receptor) and sodium fluoride (marker of bone matrix) are also mentioned. There is little justification for the use of FDG-PET/CT in patient with clinically T1 (< or = 2 cm) N0 tumours. Notably, it cannot be used as a substitute to SLNB "sentinel lymph node biopsy" for axillary staging due to limited sensitivity for the detection of small metastases. The case is different in higher risk patients, and especially so in patients with locally advanced disease. FDG-PET/CT in these patients might depict lymph node involvement in the level III of Berg or in supraclavicular or internal mammary basins. It might also uncover occult distant metastases, notably, early osteomedullary infiltration. Thus, for these tumors, initial PET/CT can enable better intramodality treatment planning or a change in treatment. PET/CT as a whole-body examination is also very efficient in case of suspicion of recurrence. On the other hand, many studies show that this functional imaging could be used to assess early response to neoadjuvant chemotherapy or to chemotherapy of metastatic disease. 18FDG-PET/CT could thus become an unavoidable modality to answer various clinical situations.

  7. A Comparison between 18F-FDG PET/CT Imaging and Biological and Radiological Findings in Restaging of Hepatoblastoma Patients

    PubMed Central

    Treglia, Giorgio; Pagano, Manuela; Fania, Piercarlo; Basso, Maria Eleonora; Fagioli, Franca; Ficola, Umberto

    2013-01-01

    Background. In this study we retrospectively evaluated if 18F-FDG-PET/CT provided incremental diagnostic information over CI in a group of hepatoblastoma patients performing restaging. Procedure. Nine patients (mean age: 5.9 years; range: 3.1–12 years) surgically treated for hepatoblastoma were followed up by clinical examination, serum α-FP monitoring, and US. CI (CT or MRI) and PET/CT were performed in case of suspicion of relapse. Fine-needle aspiration biopsies (FNAB) were carried out for final confirmation if the results of CI, PET/CT, and/or α-FP levels were suggestive of relapse. PET/CT and CI findings were analyzed for comparison purposes, using FNAB as reference standard. Results. α-FP level was suggestive of disease recurrence in 8/9 patients. Biopsy was performed in 8/9 cases. CI and PET/CT resulted to be concordant in 5/9 patients (CI identified recurrence of disease, but 18F-FDG-PET/CT provided a better definition of disease extent); in 4/9 cases, CI diagnostic information resulted in negative findings, whereas PET/CT correctly detected recurrence of disease. 18F-FDG-PET/CT showed an agreement of 100% (8/8) with FNAB results. Conclusions. 18F-FDG-PET/CT scan seems to better assess HB patients with respect to CI and may provide incremental diagnostic value in the restaging of this group of patients. PMID:24063012

  8. Evaluation of radiation dose and image quality of CT scan for whole-body pediatric PET/CT: A phantom study

    SciTech Connect

    Yang, Ching-Ching; Liu, Shu-Hsin; Mok, Greta S. P.; Wu, Tung-Hsin

    2014-09-15

    Purpose: This study aimed to tailor the CT imaging protocols for pediatric patients undergoing whole-body PET/CT examinations with appropriate attention to radiation exposure while maintaining adequate image quality for anatomic delineation of PET findings and attenuation correction of PET emission data. Methods: The measurements were made by using three anthropomorphic phantoms representative of 1-, 5-, and 10-year-old children with tube voltages of 80, 100, and 120 kVp, tube currents of 10, 40, 80, and 120 mA, and exposure time of 0.5 s at 1.75:1 pitch. Radiation dose estimates were derived from the dose-length product and were used to calculate risk estimates for radiation-induced cancer. The influence of image noise on image contrast and attenuation map for CT scans were evaluated based on Pearson's correlation coefficient and covariance, respectively. Multiple linear regression methods were used to investigate the effects of patient age, tube voltage, and tube current on radiation-induced cancer risk and image noise for CT scans. Results: The effective dose obtained using three anthropomorphic phantoms and 12 combinations of kVp and mA ranged from 0.09 to 4.08 mSv. Based on our results, CT scans acquired with 80 kVp/60 mA, 80 kVp/80 mA, and 100 kVp/60 mA could be performed on 1-, 5-, and 10-year-old children, respectively, to minimize cancer risk due to CT scans while maintaining the accuracy of attenuation map and CT image contrast. The effective doses of the proposed protocols for 1-, 5- and 10-year-old children were 0.65, 0.86, and 1.065 mSv, respectively. Conclusions: Low-dose pediatric CT protocols were proposed to balance the tradeoff between radiation-induced cancer risk and image quality for patients ranging in age from 1 to 10 years old undergoing whole-body PET/CT examinations.

  9. An in vivo molecular imaging probe (18)F-Annexin B1 for apoptosis detection by PET/CT: preparation and preliminary evaluation.

    PubMed

    Wang, Ming-Wei; Wang, Fang; Zheng, Yu-Jia; Zhang, Ying-Jian; Zhang, Yong-Ping; Zhao, Qing; Shen, Clifton Kwang-Fu; Wang, Yue; Sun, Shu-Han

    2013-02-01

    There is an increasing need to develop non-invasive molecular imaging strategies for visualizing and quantifying apoptosis status of diseases (especially for cancer) for diagnosis and monitoring treatment response. Since externalization of phosphatidylserine (PS) is one of the early molecular events during apoptosis, Annexin B1 (AnxB1), a member of Annexins family with high affinity toward the head group of PS, could be a potential positron emission tomography (PET) imaging probe for imaging cell death process after labeled by positron-emitting nuclides, such as (18)F. In the present study, we investigated a novel PET probe, (18)F-labeled Annexin B1 ((18)F-AnxB1), for apoptosis imaging. (18)F-AnxB1 was prepared reliably by conjugating AnxB1 with a (18)F-tag, N-succinimidyl 4-[(18)F]fluorobenzoate ([(18)F]SFB), in a radiolabeling yield of about 20 % within 40 min. The in vitro binding of (18)F-AnxB1 with apoptotic cells induced by anti-Fas antibody showed twofold increase compared to those without treatment, confirmed by flow cytometric analysis with AnxV-FITC/PI staining. Stability tests demonstrated (18)F-AnxB1 was rather stable in vitro and in vivo without degradation. The serial (18)F-AnxB1 PET/CT scans in healthy rats outlined its biodistribution and pharmacokinetics, indicating a rapid renal clearance and predominant accumulation into kidney and bladder at 2 h p.i. (18)F-AnxB1 PET/CT imaging was successfully applied to visualize in vivo apoptosis sites in tumor induced by chemotherapy and in kidney simulated by ischemia-reperfusion injury. The high-contrast images were obtained at 2 h p.i. to delineate apoptotic tumor. Apoptotic region could be still identified by (18)F-AnxB1 PET 4 h p.i., despite the high probe retention in kidneys. In summary, we have developed (18)F-AnxB1 as a PS-specific PET probe for the apoptosis detection and quantification which could have broad applications from disease diagnosis to treatment monitoring, especially in the cases of

  10. Comparative study of ¹⁸F-FDG-PET/CT imaging and serum hTERT mRNA quantification in cancer diagnosis.

    PubMed

    Ping, Bingqiong; Tsuno, Satoshi; Wang, Xinhui; Ishihara, Yoshitaka; Yamashita, Taro; Miura, Keigo; Miyoshi, Fuminori; Shinohara, Yuki; Matsuki, Tsutomu; Tanabe, Yoshio; Tanaka, Noriaki; Ogawa, Toshihide; Shiota, Goshi; Miura, Norimasa

    2015-10-01

    We have reported on the clinical usefulness of human telomerase reverse transcriptase (hTERT) mRNA quantification in sera in patients with several cancers. Positron emission tomography-computed tomography (PET/CT) using ¹⁸F-fluorodeoxyglucose (FDG) has recently become an excellent modality for detecting cancer. We performed a diagnostic comparative study of FDG-PET/CT and hTERT mRNA quantification in patients with cancer. Four hundred seventy subjects, including 125 healthy individuals and 345 outpatients with cancer who had received medical treatments for cancer in their own or other hospitals, were enrolled. The subjects were diagnosed by FDG-PET/CT, and we measured their serum hTERT mRNA levels using real-time RT-PCR, correlating the quantified values with the clinical course. In this prospective study, we statistically assessed the sensitivity and specificity, and their clinical significance. hTERT mRNA and FDG-PET/CT were demonstrated to be correlated with the clinical parameters of metastasis and recurrence (P < 0.001), and of recurrence and tumor number in cancer compared with noncancer patients, respectively. A multivariate analysis showed a significant difference in the detection by FDG-PET/CT, ¹⁸F-FDG uptake, the detection by hTERT mRNA, and age. The use of both FDG-PET/CT and hTERT mRNA resulted in a positivity of 94.4% (221/234) for the detection of viable tumor cells. FDG-PET/CT is superior to hTERT mRNA quantification in the early detection of cancer and combinative use of FDG-PET/CT and hTERT mRNA may improve the diagnostic accuracy of cancer.

  11. Use of the FLUKA Monte Carlo code for 3D patient-specific dosimetry on PET-CT and SPECT-CT images.

    PubMed

    Botta, F; Mairani, A; Hobbs, R F; Vergara Gil, A; Pacilio, M; Parodi, K; Cremonesi, M; Coca Pérez, M A; Di Dia, A; Ferrari, M; Guerriero, F; Battistoni, G; Pedroli, G; Paganelli, G; Torres Aroche, L A; Sgouros, G

    2013-11-21

    Patient-specific absorbed dose calculation for nuclear medicine therapy is a topic of increasing interest. 3D dosimetry at the voxel level is one of the major improvements for the development of more accurate calculation techniques, as compared to the standard dosimetry at the organ level. This study aims to use the FLUKA Monte Carlo code to perform patient-specific 3D dosimetry through direct Monte Carlo simulation on PET-CT and SPECT-CT images. To this aim, dedicated routines were developed in the FLUKA environment. Two sets of simulations were performed on model and phantom images. Firstly, the correct handling of PET and SPECT images was tested under the assumption of homogeneous water medium by comparing FLUKA results with those obtained with the voxel kernel convolution method and with other Monte Carlo-based tools developed to the same purpose (the EGS-based 3D-RD software and the MCNP5-based MCID). Afterwards, the correct integration of the PET/SPECT and CT information was tested, performing direct simulations on PET/CT images for both homogeneous (water) and non-homogeneous (water with air, lung and bone inserts) phantoms. Comparison was performed with the other Monte Carlo tools performing direct simulation as well. The absorbed dose maps were compared at the voxel level. In the case of homogeneous water, by simulating 10(8) primary particles a 2% average difference with respect to the kernel convolution method was achieved; such difference was lower than the statistical uncertainty affecting the FLUKA results. The agreement with the other tools was within 3–4%, partially ascribable to the differences among the simulation algorithms. Including the CT-based density map, the average difference was always within 4% irrespective of the medium (water, air, bone), except for a maximum 6% value when comparing FLUKA and 3D-RD in air. The results confirmed that the routines were properly developed, opening the way for the use of FLUKA for patient-specific, image

  12. Use of the FLUKA Monte Carlo code for 3D patient-specific dosimetry on PET-CT and SPECT-CT images*

    PubMed Central

    Botta, F; Mairani, A; Hobbs, R F; Vergara Gil, A; Pacilio, M; Parodi, K; Cremonesi, M; Coca Pérez, M A; Di Dia, A; Ferrari, M; Guerriero, F; Battistoni, G; Pedroli, G; Paganelli, G; Torres Aroche, L A; Sgouros, G

    2014-01-01

    Patient-specific absorbed dose calculation for nuclear medicine therapy is a topic of increasing interest. 3D dosimetry at the voxel level is one of the major improvements for the development of more accurate calculation techniques, as compared to the standard dosimetry at the organ level. This study aims to use the FLUKA Monte Carlo code to perform patient-specific 3D dosimetry through direct Monte Carlo simulation on PET-CT and SPECT-CT images. To this aim, dedicated routines were developed in the FLUKA environment. Two sets of simulations were performed on model and phantom images. Firstly, the correct handling of PET and SPECT images was tested under the assumption of homogeneous water medium by comparing FLUKA results with those obtained with the voxel kernel convolution method and with other Monte Carlo-based tools developed to the same purpose (the EGS-based 3D-RD software and the MCNP5-based MCID). Afterwards, the correct integration of the PET/SPECT and CT information was tested, performing direct simulations on PET/CT images for both homogeneous (water) and non-homogeneous (water with air, lung and bone inserts) phantoms. Comparison was performed with the other Monte Carlo tools performing direct simulation as well. The absorbed dose maps were compared at the voxel level. In the case of homogeneous water, by simulating 108 primary particles a 2% average difference with respect to the kernel convolution method was achieved; such difference was lower than the statistical uncertainty affecting the FLUKA results. The agreement with the other tools was within 3–4%, partially ascribable to the differences among the simulation algorithms. Including the CT-based density map, the average difference was always within 4% irrespective of the medium (water, air, bone), except for a maximum 6% value when comparing FLUKA and 3D-RD in air. The results confirmed that the routines were properly developed, opening the way for the use of FLUKA for patient-specific, image

  13. Use of the FLUKA Monte Carlo code for 3D patient-specific dosimetry on PET-CT and SPECT-CT images

    NASA Astrophysics Data System (ADS)

    Botta, F.; Mairani, A.; Hobbs, R. F.; Vergara Gil, A.; Pacilio, M.; Parodi, K.; Cremonesi, M.; Coca Pérez, M. A.; Di Dia, A.; Ferrari, M.; Guerriero, F.; Battistoni, G.; Pedroli, G.; Paganelli, G.; Torres Aroche, L. A.; Sgouros, G.

    2013-11-01

    Patient-specific absorbed dose calculation for nuclear medicine therapy is a topic of increasing interest. 3D dosimetry at the voxel level is one of the major improvements for the development of more accurate calculation techniques, as compared to the standard dosimetry at the organ level. This study aims to use the FLUKA Monte Carlo code to perform patient-specific 3D dosimetry through direct Monte Carlo simulation on PET-CT and SPECT-CT images. To this aim, dedicated routines were developed in the FLUKA environment. Two sets of simulations were performed on model and phantom images. Firstly, the correct handling of PET and SPECT images was tested under the assumption of homogeneous water medium by comparing FLUKA results with those obtained with the voxel kernel convolution method and with other Monte Carlo-based tools developed to the same purpose (the EGS-based 3D-RD software and the MCNP5-based MCID). Afterwards, the correct integration of the PET/SPECT and CT information was tested, performing direct simulations on PET/CT images for both homogeneous (water) and non-homogeneous (water with air, lung and bone inserts) phantoms. Comparison was performed with the other Monte Carlo tools performing direct simulation as well. The absorbed dose maps were compared at the voxel level. In the case of homogeneous water, by simulating 108 primary particles a 2% average difference with respect to the kernel convolution method was achieved; such difference was lower than the statistical uncertainty affecting the FLUKA results. The agreement with the other tools was within 3-4%, partially ascribable to the differences among the simulation algorithms. Including the CT-based density map, the average difference was always within 4% irrespective of the medium (water, air, bone), except for a maximum 6% value when comparing FLUKA and 3D-RD in air. The results confirmed that the routines were properly developed, opening the way for the use of FLUKA for patient-specific, image

  14. {sup 18}F-FDG PET-CT Simulation for Non-Small-Cell Lung Cancer: Effect in Patients Already Staged by PET-CT

    SciTech Connect

    Hanna, Gerard G.; McAleese, Jonathan; Carson, Kathryn J.; Stewart, David P.; Cosgrove, Vivian P.; Eakin, Ruth L.; Zatari, Ashraf; Lynch, Tom; Jarritt, Peter H.; Young, V.A. Linda D.C.R.; O'Sullivan, Joe M.

    2010-05-01

    Purpose: Positron emission tomography (PET), in addition to computed tomography (CT), has an effect in target volume definition for radical radiotherapy (RT) for non-small-cell lung cancer (NSCLC). In previously PET-CT staged patients with NSCLC, we assessed the effect of using an additional planning PET-CT scan for gross tumor volume (GTV) definition. Methods and Materials: A total of 28 patients with Stage IA-IIIB NSCLC were enrolled. All patients had undergone staging PET-CT to ensure suitability for radical RT. Of the 28 patients, 14 received induction chemotherapy. In place of a RT planning CT scan, patients underwent scanning on a PET-CT scanner. In a virtual planning study, four oncologists independently delineated the GTV on the CT scan alone and then on the PET-CT scan. Intraobserver and interobserver variability were assessed using the concordance index (CI), and the results were compared using the Wilcoxon signed ranks test. Results: PET-CT improved the CI between observers when defining the GTV using the PET-CT images compared with using CT alone for matched cases (median CI, 0.57 for CT and 0.64 for PET-CT, p = .032). The median of the mean percentage of volume change from GTV{sub CT} to GTV{sub FUSED} was -5.21% for the induction chemotherapy group and 18.88% for the RT-alone group. Using the Mann-Whitney U test, this was significantly different (p = .001). Conclusion: PET-CT RT planning scan, in addition to a staging PET-CT scan, reduces interobserver variability in GTV definition for NSCLC. The GTV size with PET-CT compared with CT in the RT-alone group increased and was reduced in the induction chemotherapy group.

  15. Variability of Image Features Computed from Conventional and Respiratory-Gated PET/CT Images of Lung Cancer

    PubMed Central

    Oliver, Jasmine A.; Budzevich, Mikalai; Zhang, Geoffrey G.; Dilling, Thomas J.; Latifi, Kujtim; Moros, Eduardo G.

    2015-01-01

    Radiomics is being explored for potential applications in radiation therapy. How various imaging protocols affect quantitative image features is currently a highly active area of research. To assess the variability of image features derived from conventional [three-dimensional (3D)] and respiratory-gated (RG) positron emission tomography (PET)/computed tomography (CT) images of lung cancer patients, image features were computed from 23 lung cancer patients. Both protocols for each patient were acquired during the same imaging session. PET tumor volumes were segmented using an adaptive technique which accounted for background. CT tumor volumes were delineated with a commercial segmentation tool. Using RG PET images, the tumor center of mass motion, length, and rotation were calculated. Fifty-six image features were extracted from all images consisting of shape descriptors, first-order features, and second-order texture features. Overall, 26.6% and 26.2% of total features demonstrated less than 5% difference between 3D and RG protocols for CT and PET, respectively. Between 10 RG phases in PET, 53.4% of features demonstrated percent differences less than 5%. The features with least variability for PET were sphericity, spherical disproportion, entropy (first and second order), sum entropy, information measure of correlation 2, Short Run Emphasis (SRE), Long Run Emphasis (LRE), and Run Percentage (RPC); and those for CT were minimum intensity, mean intensity, Root Mean Square (RMS), Short Run Emphasis (SRE), and RPC. Quantitative analysis using a 3D acquisition versus RG acquisition (to reduce the effects of motion) provided notably different image feature values. This study suggests that the variability between 3D and RG features is mainly due to the impact of respiratory motion. PMID:26692535

  16. Novel 18F labeling strategy for polyester-based NPs for in vivo PET-CT imaging.

    PubMed

    Di Mauro, Primiano Pio; Gómez-Vallejo, Vanessa; Baz Maldonado, Zuriñe; Llop Roig, Jordi; Borrós, Salvador

    2015-03-18

    Drug-loaded nanocarriers and nanoparticulate systems used for drug release require a careful in vivo evaluation in terms of physicochemical and pharmacokinetic properties. Nuclear imaging techniques such as positron emission tomography (PET) are ideal and noninvasive tools to investigate the biodistribution and biological fate of the nanostructures, but the incorporation of a positron emitter is required. Here we describe a novel approach for the (18)F-radiolabeling of polyester-based nanoparticles. Our approach relies on the preparation of the radiolabeled active agent 4-[(18)F]fluorobenzyl-2-bromoacetamide ([(18)F]FBBA), which is subsequently coupled to block copolymers under mild conditions. The labeled block copolymers are ultimately incorporated as constituent elements of the NPs by using a modified nano coprecipitation method. This strategy has been applied in the current work to the preparation of peptide-functionalized NPs with potential applications in drug delivery. According to the measurements of particle size and zeta potential, the radiolabeling process did not result in a statistically significant alteration of the physicochemical properties of the NPs. Moreover, radiochemical stability studies showed no detachment of the radioactivity from NPs even at 12 h after preparation. The radiolabeled NPs enabled the in vivo quantification of the biodistribution data in rats using a combination of imaging techniques, namely, PET and computerized tomography (CT). Low accumulation of the nanoparticles in the liver and their elimination mainly via urine was found. The different biodistribution pattern obtained for the "free" radiolabeled polymer suggests chemical and radiochemical integrity of the NPs under investigation. The strategy reported here may be applied to any polymeric NPs containing polymers bearing a nucleophile, and hence our novel strategy may find application for the in vivo and noninvasive investigation of a wide range of NPs.

  17. Utility of PET/CT Imaging Performed Early After Surgical Resection in the Adjuvant Treatment Planning for Head and Neck Cancer

    SciTech Connect

    Shintani, Stephanie A.; Foote, Robert L. Lowe, Val J.; Brown, Paul D.; Garces, Yolanda I.; Kasperbauer, Jan L.

    2008-02-01

    Purpose: To evaluate the utility of positron emission tomography (PET)/computed tomography (CT) early after surgical resection and before postoperative adjuvant radiation therapy. Methods and Materials: We studied a prospective cohort of 91 consecutive patients referred for postoperative adjuvant radiation therapy after complete surgical resection. Tumor histologies included 62 squamous cell and 29 non-squamous cell cancers. Median time between surgery and postoperative PET/CT was 28 days (range, 13-75 days). Findings suspicious for persistent/recurrent cancer or distant metastasis were biopsied. Correlation was made with changes in patient care. Results: Based on PET/CT findings, 24 patients (26.4%) underwent biopsy of suspicious sites. Three patients with suspicious findings did not undergo biopsy because the abnormalities were not easily accessible. Eleven (45.8%) biopsies were positive for cancer. Treatment was changed for 14 (15.4%) patients (11 positive biopsy and 3 nonbiopsied patients) as a result. Treatment changes included abandonment of radiation therapy and switching to palliative chemotherapy or hospice care (4), increasing the radiation therapy dose (6), extending the radiation therapy treatment volume and increasing the dose (1), additional surgery (2), and adding palliative chemotherapy to palliative radiation therapy (1). Treatment for recurrent cancer and primary skin cancer were significant predictors of having a biopsy-proven, treatment-changing positive PET/CT (p < 0.03). Conclusions: Even with an expectedly high rate of false positive PET/CT scans in this early postoperative period, PET/CT changed patient management in a relatively large proportion of patients. PET/CT can be recommended in the postoperative, preradiation therapy setting with the understanding that treatment-altering PET/CT findings should be biopsied for confirmation.

  18. Anxiety in Cancer Patients during 18F-FDG PET/CT Low Dose: A Comparison of Anxiety Levels before and after Imaging Studies

    PubMed Central

    Vieira, Lina; Carolino, Elisabete; Oliveira, Cátia; Pacheco, Carolina; Castro, Maria; Alonso, Juan

    2017-01-01

    Objective. Assessing the level of anxiety in oncology patients who underwent 18F-FDG PET/CT low dose scan and identifying the main reasons that generate anxiety. Material and Method. The study included 81 cancer patients submitted to the 18F-FDG PET/CT low dose scan. Patients filled in the Scan Experience Questionnaire and the State-Trait Anxiety Inventory (STAI) before and after 18F-FDG PET/CT low dose scan. Results. Substantial levels of anxiety were detected both before and after 18F-FDG PET/CT low dose scan (STAI mean > 30), with a significant increase in the state of anxiety after scan performance (p < 0.0001, Medianpre = 31.1, and Medianpos = 33.0). 18F-FDG PET/CT low dose results are the main cause of anxiety both before (79.1%) and after (86.9%) the scan. The information provided by staff both before and on the 18F-FDG PET/CT low dose day was classified mostly as completely understandable (70.5% and 75.3%, resp.) and as very useful (70.5% and 72.6%, resp.) and correlated positively with patients' overall satisfaction with NM Department (rS = 0.372, p = 0.004 and rS = 0.528, p = 0.000, resp.), but not with anxiety levels. Conclusions. Patients perceive high levels of anxiety during the 18F-FDG PET/CT low dose scan and the concern with scan results was pointed out as the main factor for that emotional reaction. PMID:28392942

  19. SU-E-J-250: A Methodology for Active Bone Marrow Protection for Cervical Cancer Intensity-Modulated Radiotherapy Using 18F-FLT PET/CT Image

    SciTech Connect

    Ma, C; Yin, Y

    2014-06-01

    Purpose: The purpose of this study was to compare a radiation therapy treatment planning that would spare active bone marrow and whole pelvic bone marrow using 18F FLT PET/CT image. Methods: We have developed an IMRT planning methodology to incorporate functional PET imaging using 18F FLT/CT scans. Plans were generated for two cervical cancer patients, where pelvicactive bone marrow region was incorporated as avoidance regions based on the range: SUV>2., another region was whole pelvic bone marrow. Dose objectives were set to reduce the volume of active bone marrow and whole bone marraw. The volumes of received 10 (V10) and 20 (V20) Gy for active bone marrow were evaluated. Results: Active bone marrow regions identified by 18F FLT with an SUV>2 represented an average of 48.0% of the total osseous pelvis for the two cases studied. Improved dose volume histograms for identified bone marrow SUV volumes and decreases in V10(average 18%), and V20(average 14%) were achieved without clinically significant changes to PTV or OAR doses. Conclusion: Incorporation of 18F FLT/CT PET in IMRT planning provides a methodology to reduce radiation dose to active bone marrow without compromising PTV or OAR dose objectives in cervical cancer.

  20. 3D inpatient dose reconstruction from the PET-CT imaging of {sup 90}Y microspheres for metastatic cancer to the liver: Feasibility study

    SciTech Connect

    Fourkal, E.; Veltchev, I.; Lin, M.; Meyer, J.; Koren, S.; Doss, M.; Yu, J. Q.

    2013-08-15

    Purpose: The introduction of radioembolization with microspheres represents a significant step forward in the treatment of patients with metastatic disease to the liver. This technique uses semiempirical formulae based on body surface area or liver and target volumes to calculate the required total activity for a given patient. However, this treatment modality lacks extremely important information, which is the three-dimensional (3D) dose delivered by microspheres to different organs after their administration. The absence of this information dramatically limits the clinical efficacy of this modality, specifically the predictive power of the treatment. Therefore, the aim of this study is to develop a 3D dose calculation technique that is based on the PET imaging of the infused microspheres.Methods: The Fluka Monte Carlo code was used to calculate the voxel dose kernel for {sup 90}Y source with voxel size equal to that of the PET scan. The measured PET activity distribution was converted to total activity distribution for the subsequent convolution with the voxel dose kernel to obtain the 3D dose distribution. In addition, dose-volume histograms were generated to analyze the dose to the tumor and critical structures.Results: The 3D inpatient dose distribution can be reconstructed from the PET data of a patient scanned after the infusion of microspheres. A total of seven patients have been analyzed so far using the proposed reconstruction method. Four patients underwent treatment with SIR-Spheres for liver metastases from colorectal cancer and three patients were treated with Therasphere for hepatocellular cancer. A total of 14 target tumors were contoured on post-treatment PET-CT scans for dosimetric evaluation. Mean prescription activity was 1.7 GBq (range: 0.58–3.8 GBq). The resulting mean maximum measured dose to targets was 167 Gy (range: 71–311 Gy). Mean minimum dose to 70% of target (D70) was 68 Gy (range: 25–155 Gy). Mean minimum dose to 90% of target

  1. 18F-FDG PET/CT in Bladder Cancer.

    PubMed

    Tagliabue, Luca; Russo, Giovanna; Lucignani, Giovanni

    2016-12-01

    Urinary clearance of F-FDG and variability in bladder wall FDG uptake may hamper the interpretation and limit the use of FDG-PET/CT for imaging bladder tumors. Nevertheless, careful combined evaluation of both CT and FDG-PET images of the urinary tract can provide useful findings. We present 2 cases of bladder cancer detected by FDG-PET/CT. These cases suggest that FDG uptake can be indicative of malignancy in bladder cancer when viewed in conjunction with CT scans and that whole-body FDG-PET/CT scans should always be reviewed with particular attention to the urinary tract because abnormalities suggestive of bladder cancer can be found unexpectedly.

  2. The contribution of PET/CT to improved patient management.

    PubMed

    Ell, P J

    2006-01-01

    With the introduction of both SPET/CT and PET/CT, multimodality imaging has truly entered routine clinical practice. Multiple slice spiral CT scanners have been incorporated with multiple detector gamma cameras or PET systems, such that the benefit of these modalities can be achieved in one patient sitting. The subject of this manuscript is PET/CT and its impact on patient management. Applications of PET/CT span the whole field of medical and surgical oncology since very few cancers do not take up the labelled glucose tracer, (18)F-FDG. Given the contrast achieved, high-quality data can be obtained with FDG PET/CT. This technology has now spread worldwide and has been the subject of intense interest, as witnessed by the vast body of published evidence. In this short overview, only a brief discussion of the main clinical applications is possible. Novel applications of PET/CT outside the field of oncology are expected in the near future.

  3. PET/CT in renal, bladder and testicular cancer

    PubMed Central

    Bouchelouche, Kirsten; Physician, Chief; Choyke, Peter L.

    2015-01-01

    Imaging plays an important role in the clinical management of cancer patients. Hybrid imaging with PET/CT is having a broad impact in oncology, and in recent years PET/CT is beginning to have an impact in uro-oncology as well. In both bladder and renal cancer there is a need to study the efficacy of other tracers than F-18 fluorodeoxyglucose (FDG), particularly tracers with only limited renal excretion. Thus, new tracers are being introduced in these malignancies. This review focuses on the clinical role of FDG and other PET agents in renal, bladder and testicular cancer. PMID:26099672

  4. Estimation of patient radiation dose from whole body 18F- FDG PET/CT examination in cancer imaging: a preliminary study

    NASA Astrophysics Data System (ADS)

    Mahmud, M. H.; Nordin, A. J.; Saad, F. F. Ahmad; Fattah Azman, A. Z.

    2014-11-01

    This study aims to estimate the radiation effective dose resulting from whole body fluorine-18 flourodeoxyglucose Positron Emission Tomography (18F-FDG PET) scanning as compared to conservative Computed Tomography (CT) techniques in evaluating oncology patients. We reviewed 19 oncology patients who underwent 18F-FDG PET/CT at our centre for cancer staging. Internal and external doses were estimated using radioactivity of injected FDG and volume CT Dose Index (CTDIvol), respectively with employment of the published and modified dose coefficients. The median differences of dose among the conservative CT and PET protocols were determined using Kruskal Wallis test with p < 0.05 considered as significant. The median (interquartile range, IQR) effective doses of non-contrasted CT, contrasted CT and PET scanning protocols were 7.50 (9.35) mSv, 9.76 (3.67) mSv and 6.30 (1.20) mSv, respectively, resulting in the total dose of 21.46 (8.58) mSv. Statistically significant difference was observed in the median effective dose between the three protocols (p < 0.01). The effective doses of whole body 18F-FDG PET technique may be effective the lowest amongst the conventional CT imaging techniques.

  5. Cerebellar Metastases From Prostate Cancer on 68Ga-PSMA PET/CT.

    PubMed

    Chan, Mico; Hsiao, Edward; Turner, Jennifer

    2017-03-01

    Ga prostate-specific membrane antigen PET/CT is increasingly used to evaluate extent of disease in prostate carcinoma. Parenchymal brain metastases originating from prostate cancer have highly variable imaging appearance. We present a 77-year-old man with cerebellar metastasis from prostate cancer showing focal uptake on prostate-specific membrane antigen PET/CT.

  6. A rare adult renal neuroblastoma better imaged by (18)F-FDG than by (68)Ga-dotanoc in the PET/CT scan.

    PubMed

    Jain, Tarun Kumar; Singh, Sharwan Kumar; Sood, Ashwani; Ashwathanarayama, Abhiram Gj; Basher, Rajender Kumar; Shukla, Jaya; Mittal, Bhagwant Rai

    2017-03-20

    Primary renal neuroblastoma is an uncommon tumor in children and extremely rare in adults. We present a case of a middle aged female having a large retroperitoneal mass involving the right kidney with features of neuroblastoma on pre-operative histopathology. Whole-body fluorine-18-fluoro-deoxyglucose positron emission tomography ((18)F-FDG PET/CT) and (68)Ga-dotanoc PET/CT scans performed for staging and therapeutic potential revealed a tracer avid mass replacing the right kidney and also pelvic lymph nodes. The (18)F-FDG PET/CT scan showed better both the primary lesion and the metastases in the pelvic lymph nodes than the (68)Ga-dotanoc scan supporting diagnosis and treatment planning.

  7. Investigating the limits of PET/CT imaging at very low true count rates and high random fractions in ion-beam therapy monitoring

    SciTech Connect

    Kurz, Christopher Bauer, Julia; Conti, Maurizio; Guérin, Laura; Eriksson, Lars; Parodi, Katia

    2015-07-15

    Purpose: External beam radiotherapy with protons and heavier ions enables a tighter conformation of the applied dose to arbitrarily shaped tumor volumes with respect to photons, but is more sensitive to uncertainties in the radiotherapeutic treatment chain. Consequently, an independent verification of the applied treatment is highly desirable. For this purpose, the irradiation-induced β{sup +}-emitter distribution within the patient is detected shortly after irradiation by a commercial full-ring positron emission tomography/x-ray computed tomography (PET/CT) scanner installed next to the treatment rooms at the Heidelberg Ion-Beam Therapy Center (HIT). A major challenge to this approach is posed by the small number of detected coincidences. This contribution aims at characterizing the performance of the used PET/CT device and identifying the best-performing reconstruction algorithm under the particular statistical conditions of PET-based treatment monitoring. Moreover, this study addresses the impact of radiation background from the intrinsically radioactive lutetium-oxyorthosilicate (LSO)-based detectors at low counts. Methods: The authors have acquired 30 subsequent PET scans of a cylindrical phantom emulating a patientlike activity pattern and spanning the entire patient counting regime in terms of true coincidences and random fractions (RFs). Accuracy and precision of activity quantification, image noise, and geometrical fidelity of the scanner have been investigated for various reconstruction algorithms and settings in order to identify a practical, well-suited reconstruction scheme for PET-based treatment verification. Truncated listmode data have been utilized for separating the effects of small true count numbers and high RFs on the reconstructed images. A corresponding simulation study enabled extending the results to an even wider range of counting statistics and to additionally investigate the impact of scatter coincidences. Eventually, the recommended

  8. The role of 18FDG, 18FDOPA PET/CT and 99mTc bone scintigraphy imaging in Erdheim-Chester disease.

    PubMed

    García-Gómez, F J; Acevedo-Báñez, I; Martínez-Castillo, R; Tirado-Hospital, J L; Cuenca-Cuenca, J I; Pachón-Garrudo, V M; Álvarez-Pérez, R M; García-Jiménez, R; Rivas-Infante, E; García-Morillo, J S; Borrego-Dorado, I

    2015-08-01

    Erdheim-Chester disease (ECD) is a rare non-Langerhans cell histiocitosis, characterized by multisystemic xanthogranulomatous infiltration by foamy histiocytes that stain positively for CD68 marker but not express CD1a and S100 proteins. Etiology and pathogenesis are still unknown and only about 500 cases are related in the literature. Multisystemic involvement leads to a wide variety of clinical manifestations that results in a poor prognosis although recent advances in treatment. We present the clinical, nuclear medicine findings and therapeutic aspects of a serie of 6 patients with histopathological diagnosis of ECD, who have undergone both bone scintigraphy (BS) and 18F-fluorodeoxyglucose (18FDG)-PET/CT scans in our institution. A complementary 18F-fluorodopa (18FDOPA)-PET/CT was performed in one case. Three different presentations of the disease were observed in our casuistic: most indolent form was a cutaneous confined disease, presented in only one patient. Multifocal involvement with central nervous system (CNS) preservation was observed in two patients. Most aggressive form consisted in a systemic involvement with CNS infiltration, presented in three patients. In our experience neurological involvement, among one case with isolate pituitary infiltration, was associated with mortality in all cases. 18FDG-PET/CT and BS were particularly useful in despite systemic involvement; locate the site for biopsy and the treatment response evaluation. By our knowledge, 18FDOPA-PET/CT not seems useful in the initial staging of ECD. A baseline 18FDG-PET/CT and BS may help in monitoring the disease and could be considered when patients were incidentally diagnosed and periodically 18FDG-PET/CT must be performed in the follow up to evaluate treatment response.

  9. PET/CT and radiotherapy in prostate cancer.

    PubMed

    De Jong, I J; De Haan, T D; Wiegman, E M; Van Den Bergh, A C M; Pruim, J; Breeuwsma, A J

    2010-10-01

    Radiotherapy is one of the corner stone treatments for patients with prostate cancer. Especially for locally advanced tumors radiotherapy +/- adjuvant androgen deprivation treatment is standard of care. This brings up the need for accurate assessment of extra prostatic tumor growth and/or the presence of nodal metastases for selection of the optimal radiation dose and treatment volume. Morphological imaging like transrectal ultra sound, computed tomography (CT) and magnetic resonance imaging (MRI) are routinely used but are limited in their accuracy in detecting extra prostatic extension and nodal metastases. In this article we present a structured review of the literature on positron emission tomography (PET)/CT and radiotherapy in prostate cancer patients with emphasis on: 1) the pretreatment assessment of extra prostatic tumor extension, nodal and distant metastases; 2) the intraprostatic tumor characterization and radiotherapy treatment planning; and 3) treatment evaluation and the use of PET/CT in guidance of salvage treatment. PET/CT is not an appropriate imaging technique for accurate T-staging of prostate cancer prior to radiotherapy. Although macroscopic disease beyond the prostatic capsule and into the periprostatic fat or in seminal vesicle is often accurately detected, the microscopic extension of prostate cancer remains undetected. Choline PET/CT holds a great potential as a single step diagnostic procedure of lymph nodes and skeleton, which could facilitate radiotherapy treatment planning. At present the use of PET/CT for treatment planning in radiotherapy is still experimental. Choline PET based tumor delineation is not yet standardized and different segmentation-algorithms are under study. However, dose escalation using dose-painting is feasible with only limited increases of the doses to the bladder and rectum wall. PET/CT using either acetate or choline is able to detect recurrent prostate cancer after radiotherapy but stratification of patients

  10. Impact of (18)F-FDG PET/CT imaging in therapeutic decisions for malignant solitary fibrous tumor of the pelvis.

    PubMed

    Yan, Jinchun; Jones, Robin L; Lewis, David H; Eary, Janet F

    2013-06-01

    The decision to give neoadjuvant chemotherapy in patients with localized high-risk soft tissue sarcoma is often based on tumor grade evaluated from biopsies, but biopsies can have the inherent issue of sampling bias. Incorporation of SUVmax and heterogeneity assessed by F-FDG PET/CT could be other crucial components in the effort to tailor treatment to an individual patient, providing valuable parameters to guide the selection of the most appropriate management schedule for an individual. We present 1 representative case describing how FDG PET/CT can assist in clinical management decisions for treatment of malignant solitary fibrous tumor of the pelvis.

  11. FDG PET/CT images demonstrating epididymo-orchitis in a patient with HIV, acute kidney injury and known epididymo-orchitis on scrotal ultrasound.

    PubMed

    Chopra, Sameer; Dharmaraja, Arjuna; Mehta, Pareen; Colletti, Patrick M; Wassef, Heidi

    2015-02-01

    A 52-year-old man with HIV was referred for an F-FDG PET/CT scan for the cause of kidney injury. FDG PET/CT scan revealed increased renal cortical FDG activity, which can be seen in HIV nephropathy or acute interstitial nephritis. Diffuse increased FDG uptake was demonstrated within the right testicle and epididymis, consistent with the patient's known right epididymo-orchitis, as diagnosed on ultrasound 1 week before admission. Multiple enlarged lymph nodes with increased FDG activity were also found within the right inguinal and external iliac nodal chains, which were presumed to be reactive. The patient was treated with ciprofloxacin with symptomatic improvement.

  12. PET/CT in paediatric malignancies - An update

    PubMed Central

    Padma, Subramanyam; Sundaram, Palaniswamy Shanmuga; Tewari, Anshu

    2016-01-01

    18F-fluorodeoxyglucose positron emission tomography (FDG-PET) is a well-established imaging modality in adult oncological practice. Its role in childhood malignancies needs to be discussed as paediatric malignancies differ from adults in tumor subtypes and they have different tumor biology and FDG uptake patterns. This is also compounded by smaller body mass, dosimetric restrictions, and physiological factors that can affect the FDG uptake. It calls for careful planning of the PET study, preparing the child, the parents, and expertise of nuclear physicians in reporting pediatric positron emission tomography/computed tomography (PET/CT) studies. In a broad perspective, FDG-PET/CT has been used in staging, assessment of therapy response, identifying metastases and as a follow-up tool in a wide variety of pediatric malignancies. This review outlines the role of PET/CT in childhood malignancies other than hematological malignancies such as lymphoma and leukemia. PMID:27688605

  13. Ga-68 DOTANOC PET/CT imaging in detection of primary site in patients with metastatic neuroendocrine tumours of unknown origin and its impact on clinical decision making: experience from a tertiary care centre in India

    PubMed Central

    Pankaj, Promila; Verma, Ritu; Jain, Anjali; Belho, Ethel S.; Mahajan, Harsh

    2016-01-01

    Background Neuroendocrine tumours (NETs) are rare, heterogeneous group of tumours which usually originate from small, occult primary sites and are characterized by over-expression of somatostatin receptors (SSTRs). Positron emission tomography/computed tomography (PET/CT) using Ga-68-labeled-somatostatin-analogues have shown superiority over other modalities for imaging of NETs. The objective of the study was to retrospectively evaluate the efficacy of Ga-68 DOTANOC PET/CT imaging in detecting the primary site in patients with metastatic NETs of unknown origin and its impact on clinical decision making in such patients. Methods Between December 2011 and September 2014, a total of 263 patients underwent Ga-68 DOTANOC PET/CT study in our department for various indications. Out of them, 68 patients (45 males, 23 females; mean age, 54.9±10.7 years; range, 31–78 years) with histopathologically proven metastatic NETs and unknown primary site (CUP-NET) on conventional imaging, who underwent Ga-68 DOTANOC PET/CT scan as part of their clinical work-up were included for analyses. Histopathology (wherever available) and/or follow-up imaging were taken as reference standard. Quantitative estimation of SSTR expression in the form of maximal standardized uptake value (SUVmax) of detected primary and metastatic sites was calculated. Follow-up data of individual patients was collected through careful survey of hospital medical records and telephonic interviews. Results Maximum patients presented to our department with hepatic metastasis (50 out of 68 patients) and grade I NETs (>50%). Ga-68 DOTANOC PET/CT scan identified primary sites in 40 out of these 68 patients i.e., in approximately 59% patients. Identified primary sites were: small intestine [19], rectum [8], pancreas [7], stomach [4], lung [1] and one each in rare sites in kidney and prostate. In one patient, 2 primary sites were identified (one each in stomach and duodenum). Mean SUVmax of the detected primary sites was

  14. Staging of Primary Abdominal Lymphomas: Comparison of Whole-Body MRI with Diffusion-Weighted Imaging and 18F-FDG-PET/CT

    PubMed Central

    Stecco, Alessandro; Buemi, Francesco; Quagliozzi, Martina; Lombardi, Mariangela; Santagostino, Alberto; Sacchetti, Gian Mauro; Carriero, Alessandro

    2015-01-01

    Background. The purpose of this study was to compare the accuracy of whole-body MRI with diffusion-weighted sequences (WB-DW-MRI) with that of 18F-FDG-PET/CT in the staging of patients with primary gastrointestinal lymphoma. Methods. This retrospective study involved 17 untreated patients with primary abdominal gastrointestinal lymphoma. All patients underwent 18F-FDG-PET/CT and WB-DW-MRI. Histopathology findings or at least 6 months of clinical and radiological follow-up was the gold standard. The Musshoff-modified Ann Arbor system was used for staging, and diagnostic accuracy was evaluated on a per-node basis. Results. WB-DW-MRI exhibited 100% sensitivity, 96.3% specificity, and 96.1% and 100% positive and negative predictive values (PPV and NPV), respectively. The sensitivity, specificity, and PPV and NPV of PET/CT were 95.9%, 100%, and 100% and 96.4%, respectively. There were no statistically significant differences between the two techniques (p = 0.05). The weighted kappa agreement statistics with a 95% confidence interval were 0.97 (0.95–0.99) between the two MRI readers and 0.87 (0.82–0.92) between the two methods. Conclusions. WB-DW-MRI appears to have a comparable diagnostic value to 18F-FDG-PET/CT in staging patients with gastrointestinal lymphoma. PMID:26798331

  15. Imaging the Normal and Abnormal Anatomy of the Female Pelvis Using (18)F FDG-PET/CT, Including Pitfalls and Artifacts.

    PubMed

    Even-Sapir, Einat

    2010-10-01

    This article summarizes the normal biodistribution of (18)F fluorodeoxyglucose in the pelvis, physiologic changes in the female reproductive system and benign adnexal and uterine lesions which may be associated with increased tracer uptake that should be appreciated when PET/CT studies of female patients, mainly those with gynecologic malignancies are reviewed.

  16. WE-AB-204-03: A Novel 3D Printed Phantom for 4D PET/CT Imaging and SIB Radiotherapy Verification

    SciTech Connect

    Soultan, D; Murphy, J; Moiseenko, V; Cervino, L; Gill, B

    2015-06-15

    Purpose: To construct and test a 3D printed phantom designed to mimic variable PET tracer uptake seen in lung tumor volumes. To assess segmentation accuracy of sub-volumes of the phantom following 4D PET/CT scanning with ideal and patient-specific respiratory motion. To plan, deliver and verify delivery of PET-driven, gated, simultaneous integrated boost (SIB) radiotherapy plans. Methods: A set of phantoms and inserts were designed and manufactured for a realistic representation of lung cancer gated radiotherapy steps from 4D PET/CT scanning to dose delivery. A cylindrical phantom (40x 120 mm) holds inserts for PET/CT scanning. The novel 3D printed insert dedicated to 4D PET/CT mimics high PET tracer uptake in the core and lower uptake in the periphery. This insert is a variable density porous cylinder (22.12×70 mm), ABS-P430 thermoplastic, 3D printed by uPrint SE Plus with inner void volume (5.5×42 mm). The square pores (1.8×1.8 mm2 each) fill 50% of outer volume, resulting in a 2:1 SUV ratio of PET-tracer in the void volume with respect to porous volume. A matching in size cylindrical phantom is dedicated to validate gated radiotherapy. It contains eight peripheral holes matching the location of the porous part of the 3D printed insert, and one central hole. These holes accommodate adaptors for Farmer-type ion chamber and cells vials. Results: End-to-end test were performed from 4D PET/CT scanning to transferring data to the planning system and target volume delineation. 4D PET/CT scans were acquired of the phantom with different respiratory motion patterns and gating windows. A measured 2:1 18F-FDG SUV ratio between inner void and outer volume matched the 3D printed design. Conclusion: The novel 3D printed phantom mimics variable PET tracer uptake typical of tumors. Obtained 4D PET/CT scans are suitable for segmentation, treatment planning and delivery in SIB gated treatments of NSCLC.

  17. Impact of FDG-PET/CT on Radiotherapy Volume Delineation in Non-Small-Cell Lung Cancer and Correlation of Imaging Stage With Pathologic Findings

    SciTech Connect

    Faria, Sergio L. Menard, Sonia; Devic, Slobodan; Sirois, Christian; Souhami, Luis; Lisbona, Robert; Freeman, Carolyn R.

    2008-03-15

    Purpose: Fluorodeoxyglucose-positron emission tomography (FDG-PET)/computed tomography (CT) is more accurate than CT in determining the extent of non-small-cell lung cancer. We performed a study to evaluate the impact of FDG-PET/CT on the radiotherapy volume delineation compared with CT without using any mathematical algorithm and to correlate the findings with the pathologic examination findings. Methods and Materials: A total of 32 patients with proven non-small-cell lung cancer, pathologic specimens from the mediastinum and lung primary, and pretreatment chest CT and FDG-PET/CT scans were studied. For each patient, two data sets of theoretical gross tumor volumes were contoured. One set was determined using the chest CT only, and the second, done separately, was based on the co-registered FDG-PET/CT data. The disease stage of each patient was determined using the TNM staging system for three data sets: the CT scan only, FDG-PET/CT scan, and pathologic findings. Results: Pathologic examination altered the CT-determined stage in 22 (69%) of 32 patients and the PET-determined stage in 16 (50%) of 32 patients. The most significant alterations were related to the N stage. PET altered the TNM stage in 15 (44%) of 32 patients compared with CT alone, but only 7 of these 15 alterations were confirmed by the pathologic findings. With respect to contouring the tumor volume for radiotherapy, PET altered the contour in 18 (56%) of 32 cases compared with CT alone. Conclusion: The contour of the tumor volume of non-small-cell lung cancer patients with co-registered FDG-PET/CT resulted in >50% alterations compared with CT targeting, findings similar to those of other publications. However, the significance of this change is unknown. Furthermore, pathologic examination showed that PET is not always accurate and histologic examination should be obtained to confirm the findings of PET whenever possible.

  18. Single scan parameterization of space-variant point spread functions in image space via a printed array: the impact for two PET/CT scanners.

    PubMed

    Kotasidis, F A; Matthews, J C; Angelis, G I; Noonan, P J; Jackson, A; Price, P; Lionheart, W R; Reader, A J

    2011-05-21

    Incorporation of a resolution model during statistical image reconstruction often produces images of improved resolution and signal-to-noise ratio. A novel and practical methodology to rapidly and accurately determine the overall emission and detection blurring component of the system matrix using a printed point source array within a custom-made Perspex phantom is presented. The array was scanned at different positions and orientations within the field of view (FOV) to examine the feasibility of extrapolating the measured point source blurring to other locations in the FOV and the robustness of measurements from a single point source array scan. We measured the spatially-variant image-based blurring on two PET/CT scanners, the B-Hi-Rez and the TruePoint TrueV. These measured spatially-variant kernels and the spatially-invariant kernel at the FOV centre were then incorporated within an ordinary Poisson ordered subset expectation maximization (OP-OSEM) algorithm and compared to the manufacturer's implementation using projection space resolution modelling (RM). Comparisons were based on a point source array, the NEMA IEC image quality phantom, the Cologne resolution phantom and two clinical studies (carbon-11 labelled anti-sense oligonucleotide [(11)C]-ASO and fluorine-18 labelled fluoro-l-thymidine [(18)F]-FLT). Robust and accurate measurements of spatially-variant image blurring were successfully obtained from a single scan. Spatially-variant resolution modelling resulted in notable resolution improvements away from the centre of the FOV. Comparison between spatially-variant image-space methods and the projection-space approach (the first such report, using a range of studies) demonstrated very similar performance with our image-based implementation producing slightly better contrast recovery (CR) for the same level of image roughness (IR). These results demonstrate that image-based resolution modelling within reconstruction is a valid alternative to projection

  19. Early prediction of histopathological response of rectal tumors after one week of preoperative radiochemotherapy using 18 F-FDG PET-CT imaging. A prospective clinical study

    PubMed Central

    2012-01-01

    Background Preoperative radiochemotherapy (RCT) is standard in locally advanced rectal cancer (LARC). Initial data suggest that the tumor’s metabolic response, i.e. reduction of its 18 F-FDG uptake compared with the baseline, observed after two weeks of RCT, may correlate with histopathological response. This prospective study evaluated the ability of a very early metabolic response, seen after only one week of RCT, to predict the histopathological response to treatment. Methods Twenty patients with LARC who received standard RCT regimen followed by radical surgery participated in this study. Maximum standardized uptake value (SUV-MAX), measured by PET-CT imaging at baseline and on day 8 of RCT, and the changes in FDG uptake (ΔSUV-MAX), were compared with the histopathological response at surgery. Response was classified by tumor regression grade (TRG) and by achievement of pathological complete response (pCR). Results Absolute SUV-MAX values at both time points did not correlate with histopathological response. However, patients with pCR had a larger drop in SUV-MAX after one week of RCT (median: -35.31% vs −18.42%, p = 0.046). In contrast, TRG did not correlate with ΔSUV-MAX. The changes in FGD-uptake predicted accurately the achievement of pCR: only patients with a decrease of more than 32% in SUV-MAX had pCR while none of those whose tumors did not show any decrease in SUV-MAX had pCR. Conclusions A decrease in ΔSUV-MAX after only one week of RCT for LARC may be able to predict the achievement of pCR in the post-RCT surgical specimen. Validation in a larger independent cohort is planned. PMID:22853868

  20. PET/CT: underlying physics, instrumentation, and advances.

    PubMed

    Torres Espallardo, I

    2017-01-12

    Since it was first introduced, the main goal of PET/CT has been to provide both PET and CT images with high clinical quality and to present them to radiologists and specialists in nuclear medicine as a fused, perfectly aligned image. The use of fused PET and CT images quickly became routine in clinical practice, showing the great potential of these hybrid scanners. Thanks to this success, manufacturers have gone beyond considering CT as a mere attenuation corrector for PET, concentrating instead on design high performance PET and CT scanners with more interesting features. Since the first commercial PET/CT scanner became available in 2001, both the PET component and the CT component have improved immensely. In the case of PET, faster scintillation crystals with high stopping power such as LYSO crystals have enabled more sensitive devices to be built, making it possible to reduce the number of undesired coincidence events and to use time of flight (TOF) techniques. All these advances have improved lesion detection, especially in situations with very noisy backgrounds. Iterative reconstruction methods, together with the corrections carried out during the reconstruction and the use of the point-spread function, have improved image quality. In parallel, CT instrumentation has also improved significantly, and 64- and 128-row detectors have been incorporated into the most modern PET/CT scanners. This makes it possible to obtain high quality diagnostic anatomic images in a few seconds that both enable the correction of PET attenuation and provide information for diagnosis. Furthermore, nowadays nearly all PET/CT scanners have a system that modulates the dose of radiation that the patient is exposed to in the CT study in function of the region scanned. This article reviews the underlying physics of PET and CT imaging separately, describes the changes in the instrumentation and standard protocols in a combined PET/CT system, and finally points out the most important

  1. [Role of PET-CT in the follow-up of treated tumors of the head and neck].

    PubMed

    Mabille, L

    2008-01-01

    F-18 FDG PET-CT is a well established medical imaging technique used routinely for the follow-up of treated head and neck tumors. Currently, PET-CT is performed 4 months after the end of therapy to assess its efficacy. More recently it has been suggested that this delay could be reduced to one month with major therapeutic implications. During follow-up, PET-CT could improve sensitivity and specificity compared to other imaging techniques. Moreover, since PET-CT is a "whole body technique", it allows restaging in a single procedure.

  2. Whole body 18F-FDG PET/CT is superior to CT as first line diagnostic imaging in patients referred with serious non-specific symptoms or signs of cancer: a randomized prospective study of 200 patients.

    PubMed

    Lebech, Anne-Mette; Gaardsting, Anne; Loft, Annika; Graff, Jesper; Markova, Elena; Berthelsen, Anne Kiil; Madsen, Jan Lysgaard; Helms, Morten; Mathiesen, Lars R; David, Kim P; Kronborg, Gitte; Kjaer, Andreas

    2017-01-12

    A fast-track pathway has been established in Denmark to investigate patients with serious non-specific symptoms and signs of cancer (NSSC), which are not eligible to enter an organ-specific cancer program. The prevalence of cancer in this cohort is approximately 20%. The optimal screening strategy in patients with NSSC remains unknown. The aim was to investigate if (18)F-FDG-positron emission tomography/computed tomography (PET/CT) was superior to CT as initial imaging modality in patients with NSSC. In a randomized prospective trial the imaging modalities were compared with regard to diagnostic performance.

  3. Quantification with a dedicated breast PET/CT scanner

    PubMed Central

    Bowen, Spencer L.; Ferrero, Andrea; Badawi, Ramsey D.

    2012-01-01

    Purpose: Dedicated breast PET/CT is expected to have utility in local staging, surgical planning, monitoring of therapy response, and detection of residual disease for breast cancer. Quantitative metrics will be integral to several such applications. The authors present a validation of fully 3D data correction schemes for a custom built dedicated breast PET/CT (DbPET/CT) scanner via 18F-FDG phantom scans. Methods: A component-based normalization was implemented, live-time was estimated with a multicomponent model, and a variance reduced randoms estimate was computed from delayed coincidences. Attenuation factors were calculated by using a CT based segmentation scheme while scatter was computed using a Monte Carlo (MC) simulation method. As no performance standard currently exists for breast PET systems, custom performance tests were created based on prior patient imaging results. Count-rate linearity for live-time and randoms corrections was measured with a decay experiment for a solid polyethylene cylinder phantom with an offset line source. A MC simulation was used to validate attenuation correction, a multicompartment phantom with asymmetric activity distribution provided an assessment of scatter correction, and image uniformity after geometric and detector normalization was measured from a high count scan of a uniform cylinder phantom. Raw data were reconstructed with filtered back projection (FBP) after Fourier rebinning. To quantify performance absolute activity concentrations, contrast recovery coefficients and image uniformity were calculated through region of interest analysis. Results: The most significant source of error was attributed to mispositioning of events due to pile-up, presenting in count-related axial and transaxial nonuniformities that were not corrected for with the normalization method used here. Within the range of singles counts observed during clinical trials residual error after applying all corrections was comparable to that of a

  4. Accuracy and Utility of Deformable Image Registration in {sup 68}Ga 4D PET/CT Assessment of Pulmonary Perfusion Changes During and After Lung Radiation Therapy

    SciTech Connect

    Hardcastle, Nicholas; Hofman, Michael S.; Hicks, Rodney J.; Callahan, Jason; Kron, Tomas; MacManus, Michael P.; Ball, David L.; Jackson, Price; Siva, Shankar

    2015-09-01

    Purpose: Measuring changes in lung perfusion resulting from radiation therapy dose requires registration of the functional imaging to the radiation therapy treatment planning scan. This study investigates registration accuracy and utility for positron emission tomography (PET)/computed tomography (CT) perfusion imaging in radiation therapy for non–small cell lung cancer. Methods: {sup 68}Ga 4-dimensional PET/CT ventilation-perfusion imaging was performed before, during, and after radiation therapy for 5 patients. Rigid registration and deformable image registration (DIR) using B-splines and Demons algorithms was performed with the CT data to obtain a deformation map between the functional images and planning CT. Contour propagation accuracy and correspondence of anatomic features were used to assess registration accuracy. Wilcoxon signed-rank test was used to determine statistical significance. Changes in lung perfusion resulting from radiation therapy dose were calculated for each registration method for each patient and averaged over all patients. Results: With B-splines/Demons DIR, median distance to agreement between lung contours reduced modestly by 0.9/1.1 mm, 1.3/1.6 mm, and 1.3/1.6 mm for pretreatment, midtreatment, and posttreatment (P<.01 for all), and median Dice score between lung contours improved by 0.04/0.04, 0.05/0.05, and 0.05/0.05 for pretreatment, midtreatment, and posttreatment (P<.001 for all). Distance between anatomic features reduced with DIR by median 2.5 mm and 2.8 for pretreatment and midtreatment time points, respectively (P=.001) and 1.4 mm for posttreatment (P>.2). Poorer posttreatment results were likely caused by posttreatment pneumonitis and tumor regression. Up to 80% standardized uptake value loss in perfusion scans was observed. There was limited change in the loss in lung perfusion between registration methods; however, Demons resulted in larger interpatient variation compared with rigid and B-splines registration

  5. PSMA-Based [18F]DCFPyL PET/CT Is Superior to Conventional Imaging for Lesion Detection in Patients with Metastatic Prostate Cancer

    PubMed Central

    Rowe, Steven P.; Macura, Katarzyna J.; Mena, Esther; Blackford, Amanda L.; Nadal, Rosa; Antonarakis, Emmanuel S.; Eisenberger, Mario; Carducci, Michael; Fan, Hong; Dannals, Robert F.; Chen, Ying; Mease, Ronnie C.; Szabo, Zsolt; Pomper, Martin G.; Cho, Steve Y.

    2017-01-01

    Purpose Current standard of care conventional imaging modalities (CIM) such as X-ray computed tomography (CT) and bone scan can be limited for detection of metastatic prostate cancer and therefore improved imaging methods are an unmet clinical need. We evaluated the utility of a novel second-generation low molecular weight radiofluorinated prostate-specific membrane antigen (PSMA)-targeted positron emission tomography (PET) radiotracer, [18F]DCFPyL, in patients with metastatic prostate cancer. Procedures Nine patients with suspected prostate cancer recurrence, eight with CIM evidence of metastatic prostate cancer and one with biochemical recurrence, were imaged with [18F]DCFPyL PET/CT. Eight of the patients had contemporaneous CIM for comparison. A lesion-by-lesion comparison of the detection of suspected sites of metastatic prostate cancer was carried out between PET and CIM. Statistical analysis for estimated proportions of inter-modality agreement for detection of metastatic disease was calculated accounting for intra-patient correlation using general estimating equation (GEE) intercept-only regression models. Results One hundred thirty-nine sites of PET positive [18F]DCFPyL uptake (138 definite, 1 equivocal) for metastatic disease were detected in the eight patients with available comparison CIM. By contrast, only 45 lesions were identified on CIM (30 definite, 15 equivocal). When lesions were negative or equivocal on CIM, it was estimated that a large portion of these lesions or 0.72 (95 % confidence interval (CI) 0.55–0.84) would be positive on [18F]DCFPyL PET. Conversely, of those lesions negative or equivocal on [18F]DCFPyL PET, it was estimated that only a very small proportion or 0.03 (95 % CI 0.01–0.07) would be positive on CIM. Delayed 2-h-post-injection time point PET yielded higher tumor radiotracer uptake and higher tumor-to-background ratios than an earlier 1-h-post-injection time point. Conclusions A novel PSMA-targeted PET radiotracer, [18F

  6. Conspicuity of Malignant Lesions on PET/CT and Simultaneous Time-Of-Flight PET/MRI

    PubMed Central

    Minamimoto, Ryogo; Iagaru, Andrei; Jamali, Mehran; Holley, Dawn; Barkhodari, Amir; Vasanawala, Shreyas; Zaharchuk, Greg

    2017-01-01

    Purpose To compare the conspicuity of malignant lesions between FDG PET/CT and a new simultaneous, time-of-flight (TOF) enabled PET/MRI scanner. Methods All patients underwent a single-injection of FDG, followed by a dual imaging protocol consisting of PET/CT followed by TOF PET/MRI. PET/CT and PET/MRI images were evaluated by two readers independently for areas of FDG uptake compatible with malignancy, and then categorized into 5 groups (1: PET/MRI and PET/CT positive; 2: PET/MRI positive, PET/CT positive in retrospect; 3: PET/CT positive, PET/MRI positive in retrospect; 4: PET/MRI positive, PET/CT negative; 5: PET/MRI negative, PET/CT positive) by consensus. Patients with no lesions on either study or greater than 10 lesions based on either modality were excluded from the study. Results Fifty-two patients (mean±SD age: 58±14 years) underwent the dual imaging protocol; of these, 29 patients with a total of 93 FDG-avid lesions met the inclusion criteria. The majority of lesions (56%) were recorded prospectively in the same location on PET/CT and PET/MRI. About an equal small fraction of lesions were seen on PET/CT but only retrospectively on PET/MRI (9%) and vice versa (12%). More lesions were identified only on PET/MRI but not on PET/CT, even in retrospect (96% vs. 81%, respectively; p = 0.003). Discrepant lesions had lower maximum standardized uptake value (SUVmax) than concordant lesions on both modalities (p<0.001). Conclusions While most lesions were identified prospectively on both modalities, significantly more lesions were identified with PET/MRI than with PET/CT. PMID:28103230

  7. The effect of activity outside the field of view on image quality for a 3D LSO-based whole body PET/CT scanner.

    PubMed

    Matheoud, R; Secco, C; Della Monica, P; Leva, L; Sacchetti, G; Inglese, E; Brambilla, M

    2009-10-07

    The purpose of this study was to quantify the influence of outside field of view (FOV) activity concentration (A(c)(,out)) on the noise equivalent count rate (NECR), scatter fraction (SF) and image quality of a 3D LSO whole-body PET/CT scanner. The contrast-to-noise ratio (CNR) was the figure of merit used to characterize the image quality of PET scans. A modified International Electrotechnical Commission (IEC) phantom was used to obtain SF and counting rates similar to those found in average patients. A scatter phantom was positioned at the end of the modified IEC phantom to simulate an activity that extends beyond the scanner. The modified IEC phantom was filled with (18)F (11 kBq mL(-1)) and the spherical targets, with internal diameter (ID) ranging from 10 to 37 mm, had a target-to-background ratio of 10. PET images were acquired with background activity concentrations into the FOV (A(c)(,bkg)) about 11, 9.2, 6.6, 5.2 and 3.5 kBq mL(-1). The emission scan duration (ESD) was set to 1, 2, 3 and 4 min. The tube inside the scatter phantom was filled with activities to provide A(c)(,out) in the whole scatter phantom of zero, half, unity, twofold and fourfold the one of the modified IEC phantom. Plots of CNR versus the various parameters are provided. Multiple linear regression was employed to study the effects of A(c)(,out) on CNR, adjusted for the presence of variables (sphere ID, A(c)(,bkg) and ESD) related to CNR. The presence of outside FOV activity at the same concentration as the one inside the FOV reduces peak NECR of 30%. The increase in SF is marginal (1.2%). CNR diminishes significantly with increasing outside FOV activity, in the range explored. ESD and A(c)(,out) have a similar weight in accounting for CNR variance. Thus, an experimental law that adjusts the scan duration to the outside FOV activity can be devised. Recovery of CNR loss due to an elevated A(c)(,out) activity seems feasible by modulating the ESD in individual bed positions according to A(c)(,out).

  8. Development and preclinical studies of (64)Cu-NOTA-pertuzumab F(ab')2 for imaging changes in tumor HER2 expression associated with response to trastuzumab by PET/CT.

    PubMed

    Lam, Karen; Chan, Conrad; Reilly, Raymond M

    2017-01-01

    We previously reported that microSPECT/CT imaging with (111)In-labeled pertuzumab detected decreased HER2 expression in human breast cancer (BC) xenografts in athymic mice associated with response to treatment with trastuzumab (Herceptin). Our aim was to extend these results to PET/CT by constructing F(ab')2 of pertuzumab modified with NOTA chelators for complexing (64)Cu. The effect of the administered mass (5-200 µg) of (64)Cu-NOTA-pertuzumab F(ab')2 was studied in NOD/SCID mice engrafted with HER2-positive SK-OV-3 human ovarian cancer xenografts. Biodistribution studies were performed in non-tumor bearing Balb/c mice to predict radiation doses to normal organs in humans. Serial PET/CT imaging was conducted on mice engrafted with HER2-positive and trastuzumab-sensitive BT-474 or trastuzumab-insensitive SK-OV-3 xenografted mice treated with weekly doses of trastuzumab. There were no significant effects of the administered mass of (64)Cu-NOTA-pertuzumab F(ab')2 on tumor or normal tissue uptake. The predicted total body dose in humans was 0.015 mSv/MBq, a 3.3-fold reduction compared to (111)In-labeled pertuzumab. MicroPET/CT images revealed specific tumor uptake of (64)Cu-NOTA-pertuzumab F(ab')2 at 24 or 48 h post-injection in mice with SK-OV-3 tumors. Image analysis of mice treated with trastuzumab showed 2-fold reduced uptake of (64)Cu-NOTA-pertuzumab F(ab')2 in BT-474 tumors after 1 week of trastuzumab normalized to baseline, and 1.9-fold increased uptake in SK-OV-3 tumors after 3 weeks of trastuzumab, consistent with tumor response and resistance, respectively. We conclude that PET/CT imaging with (64)Cu-NOTA-pertuzumab F(ab')2 detected changes in HER2 expression in response to trastuzumab while delivering a lower total body radiation dose compared to (111)In-labeled pertuzumab.

  9. Occipital Hypometabolism on FDG PET/CT Scan in a Child with Hodgkin's Lymphoma

    PubMed Central

    Tatci, Ebru; Ozmen, Ozlem; Gokcek, Atila; Demir, Haci Ahmet; Gulleroglu, Nadide Basak

    2016-01-01

    It is known that Fluorodeoxyglucose (FDG) Positron Emission/Computed Tomography (PET/CT) images may be helpful for evaluation of brain function in newborns. Here we described the fluorine-18 [18-F] FDG PET/CT imaging findings of encephalomalacia due to perinatal asphyxia in a child with refractory Hodgkin's Lymphoma (HL) who underwent PET/CT scan to stage the primary disease. Prominent hypometabolism was incidentally detected in the occipital regions bilaterally apart from the FDG uptakes in the malign lymphatic infiltrations. This case highlights the potential coexistence of a malignancy and a functional brain disorder. PMID:27965911

  10. Hybrid cardiac imaging: SPECT/CT and PET/CT. A joint position statement by the European Association of Nuclear Medicine (EANM), the European Society of Cardiac Radiology (ESCR) and the European Council of Nuclear Cardiology (ECNC).

    PubMed

    Flotats, Albert; Knuuti, Juhani; Gutberlet, Matthias; Marcassa, Claudio; Bengel, Frank M; Kaufmann, Philippe A; Rees, Michael R; Hesse, Birger

    2011-01-01

    Improvements in software and hardware have enabled the integration of dual imaging modalities into hybrid systems, which allow combined acquisition of the different data sets. Integration of positron emission tomography (PET) and computed tomography (CT) scanners into PET/CT systems has shown improvement in the management of patients with cancer over stand-alone acquired CT and PET images. Hybrid cardiac imaging either with single photon emission computed tomography (SPECT) or PET combined with CT depicts cardiac and vascular anatomical abnormalities and their physiologic consequences in a single setting and appears to offer superior information compared with either stand-alone or side-by-side interpretation of the data sets in patients with known or suspected coronary artery disease (CAD). Hybrid systems are also advantageous for the patient because of the single short dual data acquisition. However, hybrid cardiac imaging has also generated controversy with regard to which patients should undergo such integrated examination for clinical effectiveness and minimization of costs and radiation dose, and if software-based fusion of images obtained separately would be a useful alternative. The European Association of Nuclear Medicine (EANM), the European Society of Cardiac Radiology (ESCR) and the European Council of Nuclear Cardiology (ECNC) in this paper want to present a position statement of the institutions on the current roles of SPECT/CT and PET/CT hybrid cardiac imaging in patients with known or suspected CAD.

  11. An emerging evidence base for PET-CT in the management of childhood rhabdomyosarcoma: systematic review

    PubMed Central

    Norman, Gill; Fayter, Debra; Lewis-Light, Kate; Chisholm, Julia; McHugh, Kieran; Levine, Daniel; Jenney, Meriel; Mandeville, Henry; Gatz, Suzanne; Phillips, Bob

    2015-01-01

    Introduction Rhabdomyosarcoma (RMS) management depends on risk stratification at diagnosis and treatment response. Assessment methods include CT, MRI, bone scintigraphy, histological analysis and bone marrow biopsy. Advanced functional imaging (FI) has potential to improve staging accuracy and management strategies. Methods and analysis We conducted a systematic review (PROSPERO 2013:CRD42013006128) of diagnostic accuracy and clinical effectiveness of FI in histologically proven paediatric RMS. PRISMA guidance was followed. We searched 10 databases to November 2013. Studies with ≥10 patients with RMS which compared positron emission tomography (PET), PET-CT or diffusion-weighted imaging (DWI) MRI to conventional imaging at any treatment stage were included. Study quality was assessed. Limited, heterogeneous effectiveness data required narrative synthesis, illustrated by plotting sensitivity and specificity in receiver operating curve (ROC) space. Results Eight studies (six PET-CT, two PET) with 272 RMS patients in total were included. No DWI-MRI studies met inclusion criteria. Pooled estimates were not calculated due to sparseness of data. Limited evidence indicated initial PET-CT results were predictive of survival. PET-CT changed management of 7/40 patients. Nodal involvement PET-CT: sensitivity ranged from 80% to 100%; specificity from 89% to 100%. Distant metastatic involvement: PET-CT sensitivity ranged from 95% to 100%; specificity from 80% to100%. Data on metastases in different sites were sparse. Limited data were found on outcome prediction by PET-CT response. Dissemination and ethics PET/PET-CT may increase initial staging accuracy in paediatric RMS, specifically in the detection of nodal involvement and distant metastatic spread. There is a need to further assess PET-CT for this population, ideally in a representative, unbiased and transparently selected cohort of patients. PMID:25573522

  12. PET/CT imaging in polymyalgia rheumatica: praepubic 18F-FDG uptake correlates with pectineus and adductor longus muscles enthesitis and with tenosynovitis

    PubMed Central

    Sprlakova-Pukova, Andrea; Bortlicek, Zbynek; Fojtik, Zdenek; Kazda, Tomas; Joukal, Marek; Koukalova, Renata; Vasina, Jiri; Eremiasova, Jana; Nemec, Petr

    2017-01-01

    Abstract Background The role of 18F-fluorodeoxyglucose positron emission computed tomography (18F-FDG PET/CT) is increasing in the diagnosis of polymyalgia rheumatica (PMR), one of the most common inflammatory rheumatic diseases. In addition to other locations, increased 18F-FDG accumulation has been detected in the praepubic region in some patients. However, a deeper description and pathophysiological explanation of this increased praepubic accumulation has been lacking. The aim of the presented study is to confirm a decrease in praepubic 18F-FDG accumulation in response to therapy and to describe potential correlations to other 18F-FDG PET/CT scan characteristics during the course of disease. As a secondary objective, we describe the pathological aspects of the observed praepubic 18F-FDG uptake. Patients and methods A retrospective review of patients with newly suspected PMR undergoing baseline and follow up 18F-FDG PET/CT between February 2010 and March 2016 is given. Those with a visually detected presence of praepubic 18F-FDG accumulation were further analysed. The uptake was assessed visually and also semi-quantitatively in the defined region of interest by calculation of target-to-liver ratios. Other regions typical for PMR were systematically described as well (shoulders, hips, sternoclavicular joints, ischiogluteal bursae, spinous interspaces). Results Twenty-three out of 89 screened patients (26%) presented with initial praepubic 18F-FDG PET/CT positivity, 15 of whom also underwent follow up 18F-FDG PET/CT examination. Five out of 15 patients presented with increased 18F-FDG accumulation in large arteries as a sign of giant cell arteritis. During follow up examination, decrease in 18F-FDG accumulation caused by therapeutic intervention was observed in all evaluated locations in all analysed patients and no new positivity was indicated, including periarticular, extraarticular tissues or target large vessels. Praepubical accumulation of 18F-FDG was

  13. Comparison of dosimetry between PET/CT and PET alone using (11)C-ITMM.

    PubMed

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

    2016-03-01

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

  14. An Assessment of Early Response to Targeted Therapy via Molecular Imaging: A Pilot Study of 3'-deoxy-3'[(18)F]-Fluorothymidine Positron Emission Tomography (18)F-FLT PET/CT in Prostate Adenocarcinoma.

    PubMed

    Kairemo, Kalevi; Ravizzini, Gregory C; Macapinlac, Homer A; Subbiah, Vivek

    2017-04-04

    Fluorothymidine is a thymidine analog labeled with fluorine-18 fluorothymidine for positron emission tomography ((18)F-FLT-PET) imaging. Thymidine is a nucleic acid that is used to build DNA. Fluorine-18 fluorothymidine ((18)F-FLT) utilizes the same metabolic pathway as does thymidine but has a very low incidence of being incorporated into the DNA (<1%). (18)F-FLT-PET could have a role in the evaluation of response to targeted therapy. We present here a pilot study where we investigated cellular metabolism and proliferation in patients with prostate cancer before and after targeted therapy. Seven patients with Stage IV prostate adenocarcinoma, candidates for targeted therapy inhibiting the hepatocyte growth factor/tyrosine-protein kinase Met (HGF/C-MET) pathway, were included in this study. The HGF/C-MET pathway is implicated in prostate cancer progression, and an evaluation of the inhibition of this pathway could be valuable. (18)F-FLT was performed at baseline and within four weeks post-therapy. Tumor response was assessed semi-quantitatively and using visual response criteria. The range of SUVmax for (18)F-FLT at baseline in the prostate varied from 2.5 to 4.2. This study demonstrated that (18)F-FLT with positron emission tomography/computerized tomography ((18)F-FLT PET/CT) had only limited applications in the early response evaluation of prostate cancer. (18)F-FLT PET/CT may have some utility in the assessment of response in lymph node disease. However, (18)F-FLT PET/CT was not found to be useful in the evaluation of the prostate bed, metastatic skeletal disease, and liver disease.

  15. Subacute Cortical Infarct Showing Uptake on 68Ga-PSMA PET/CT.

    PubMed

    Chan, Mico; Hsiao, Edward

    2017-02-01

    Ga prostate-specific membrane antigen (PSMA) PET/CT is increasingly used to evaluate extent of disease in prostate carcinoma. We present a case of subacute cortical cerebral infarct showing focal uptake on PSMA PET/CT. It is an important potential cause of false-positive uptake in this imaging cohort. The patient is an 85-year-old man with a background of nonbacterial thrombotic endocarditis and previous cerebrovascular events. He was referred for PSMA PET/CT for staging of high-risk prostate cancer.

  16. Abdomen: normal variations and benign conditions resulting in uptake on FDG-PET/CT.

    PubMed

    Zukotynski, Katherine; Kim, Chun K

    2014-04-01

    The increasing use of (18)F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) in oncology has led to: improved sensitivity and specificity in detecting localized and metastatic disease, increased ability to target biopsies to the site of most aggressive disease, and development of a noninvasive biomarker to assess prognosis and effects of therapy. However, for correct interpretation of FDG-PET/CT studies, an understanding of both normal and abnormal imaging appearances commonly encountered in oncology patients is important. This article discusses commonly seen normal variations and benign findings on FDG-PET/CT of the abdomen.

  17. 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

  18. PSMA Expression in Tumor Neovasculature Endothelial Cells of Follicular Thyroid Adenoma as Identified by Molecular Imaging Using 68Ga-PSMA Ligand PET/CT.

    PubMed

    Derlin, Thorsten; Kreipe, Hans-Heinrich; Schumacher, Udo; Soudah, Bisharah

    2017-03-01

    The prostate-specific membrane antigen (PSMA) is expressed by both prostate cancer and other neoplasms. We report the case of a 65-year-old man with castration-resistant metastatic prostate cancer who underwent Ga-PSMA ligand PET/CT for restaging of disease. Ga-PSMA ligand accumulation was noted in a thyroid lesion, suspicious for thyroid malignancy on complementary ultrasound. Subsequent resection and histopathological analysis showed follicular thyroid adenoma with PSMA expression in tumor neovasculature endothelial cells, but not in thyroid epithelial cells. It is important to be aware that both malignant and benign thyroid neoplasms may show PSMA expression to avoid misinterpretation.

  19. 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.

  20. Molecular Imaging in Neuroendocrine Differentiation of Prostate Cancer: 68 Ga-PSMA Versus 68 Ga-DOTA NOC PET-CT.

    PubMed

    Usmani, Sharjeel; Ahmed, Najeeb; Marafi, Fahad; Rasheed, Rashid; Amanguno, Henney G; Al Kandari, Fareeda

    2017-02-24

    We report on a 62-year-old man with metastatic prostate cancer (cT3b N1) diagnosed in 2011, treated with total androgen blockage with flutamide and goserelin acetate (Zoladex). He presented with left suprascapular swelling and low-back pain after being asymptomatic for 5 years. His prostate-specific antigen was 0.049 ng/mL. F-NaF PET-CT and Ga-PSMA scan were negative, whereas Ga-DOTA NOC scan done after 10 days showed multiple somatostatin-avid hepatic and lymph node metastasis.

  1. Assessment of the usefulness of the standardized uptake values and the radioactivity levels for the preoperative diagnosis of thyroid cancer measured by using 18F-FDG PET/CT dual-time-point imaging

    NASA Astrophysics Data System (ADS)

    Lee, Hyeon-Guck; Hong, Seong-Jong; Cho, Jae-Hwan; Han, Man-Seok; Kim, Tae-Hyung; Lee, Ik-Han

    2013-02-01

    The purpose of this study was to assess and compare the changes in the SUV (standardized uptake value), the 18F-FDG (18F-fluorodeoxyglucose) uptake pattern, and the radioactivity level for the diagnosis of thyroid cancer via dual-time-point 18F-FDG PET/CT (positron emission tomographycomputed tomography) imaging. Moreover, the study aimed to verify the usefulness and significance of SUV values and radioactivity levels to discriminate tumor malignancy. A retrospective analysis was performed on 40 patients who received 18F-FDG PET/CT for thyroid cancer as a primary tumor. To set the background, we compared changes in values by calculating the dispersion of scattered rays in the neck area and the lung apex, and by comparing the mean and SD (standard deviation) values of the maxSUV and the radioactivity levels. According to the statistical analysis of the changes in 18F-FDG uptake for the diagnosis of thyroid cancer, a high similarity was observed with the coefficient of determination being R2 = 0.939, in the SUVs and the radioactivity levels. Moreover, similar results were observed in the assessment of tumor malignancy using dual-time-point. The quantitative analysis method for assessing tumor malignancy using radioactivity levels was neither specific nor discriminative compared to the semi-quantitative analysis method.

  2. MIB-1 Index-Stratified Assessment of Dual-Tracer PET/CT with (68)Ga-DOTATATE and (18)F-FDG and Multimodality Anatomic Imaging in Metastatic Neuroendocrine Tumors of Unknown Primary in a PRRT Workup Setting.

    PubMed

    Sampathirao, Nikita; Basu, Sandip

    2017-03-01

    Our aim was to comparatively assess dual-tracer PET/CT ((68)Ga-DOTATATE and (18)F-FDG) and multimodality anatomic imaging in studying metastatic neuroendocrine tumors (NETs) of unknown primary (CUP-NETs) scheduled for peptide receptor radionuclide therapy for divergence of tracer uptake on dual-tracer PET/CT, detection of primary, and overall lesion detection vis-a-vis tumor proliferation index (MIB-1/Ki-67). Methods: Fifty-one patients with CUP-NETs (25 men, 26 women; age, 22-74 y), histopathologically proven and thoroughly investigated with conventional imaging modalities (ultrasonography, CT/contrast-enhanced CT, MRI, and endoscopic ultrasound, wherever applicable), were retrospectively analyzed. Patients were primarily referred for deciding on feasibility of peptide receptor radionuclide therapy (except 2 patients), and all had undergone (68)Ga-DOTATATE and (18)F-FDG PET/CT as part of pretreatment workup. The sites of metastases included liver, lung/mediastinum, skeleton, abdominal nodes, and other soft-tissue sites. Patients were divided into 5 groups on the basis of MIB-1/Ki-67 index on a 5-point scale: group I (1%-5%) (n = 35), group II (6%-10%) (n = 8), group III (11%-15%) (n = 4), group IV (16%-20%) (n = 2), and group V (>20%) (n = 2). Semiquantitative analysis of tracer uptake was undertaken by SUVmax of metastatic lesions and the primary (when detected). The SUVmax values were studied over increasing MIB-1/Ki-67 index. The detection sensitivity of (68)Ga-DOTATATE for primary and metastatic lesions was assessed and compared with other imaging modalities including (18)F-FDG PET/CT. Results: Unknown primary was detected on (68)Ga-DOTATATE in 31 of 51 patients, resulting in sensitivity of 60.78% whereas overall lesion detection sensitivity was 96.87%. The overall lesion detection sensitivities (individual groupwise from group I to group V) were 97.75%, 87.5%, 100%, 100%, and 66.67%, respectively. As MIB-1/Ki-67 index increased, (68)Ga-DOTATATE uptake

  3. FDG PET/CT dataset for navigation on femoral bone: a feasibility study.

    PubMed

    Militz, Matthias; Uhde, Jörg; Christian, Georg; Linke, Rainer; Morgenstern, Mario; Hungerer, Sven

    2015-12-01

    FDG PET/CT has become a valuable tool in the diagnosis of the activity of chronic osteomyelitis. The surgical strategy in the treatment of chronic osteomyelitis is the identification of the bone focus and radical debridement of sequesters. The aim of the current study was the registration and use of the FDG PET/CT imaging datasets on a navigation system to provide diagnostic imaging based feedback during surgical procedures. For the present study, FDG PET/CT scans were acquired from artificial bones and cadaver bones with a local focus of activity. The DICOM data sets were merged using a navigation system. The referenced regions of interest were matched with fluoroscopic pictures to register the PET/CT DICOM datasets to the bone and direct visual control. Navigated targeting led to accurate results when verified with fluoroscopic images by targeting previously inserted reference points in artificial and cadaver bone. FDG PET/CT datasets are suitable for navigation and compatible with conventional planning and navigation software. The combination of diagnostic FDG PET/CT imaging with surgical navigation techniques could be a valuable tool for the accurate treatment of chronic osteomyelitis.

  4. Bone Windows for Distinguishing Malignant from Benign Primary Bone Tumors on FDG PET/CT.

    PubMed

    Costelloe, Colleen M; Chuang, Hubert H; Chasen, Beth A; Pan, Tinsu; Fox, Patricia S; Bassett, Roland L; Madewell, John E

    2013-01-01

    Objective. The default window setting on PET/CT workstations is soft tissue. This study investigates whether bone windowing and hybrid FDG PET/CT can help differentiate between malignant and benign primary bone tumors. Materials and methods. A database review included 98 patients with malignant (n=64) or benign primary bone (n=34) tumors. The reference standard was biopsy for malignancies and biopsy or >1 year imaging follow-up of benign tumors. Three radiologists and/or nuclear medicine physicians blinded to diagnosis and other imaging viewed the lesions on CT with bone windows (CT-BW) without and then with PET (PET/CT-BW), and separate PET-only images for malignancy or benignity. Three weeks later the tumors were viewed on CT with soft tissue windows (CT-STW) without and then with PET (PET/CT-STW). Results. Mean sensitivity and specificity for identifying malignancies included: CT-BW: 96%, 90%; CT-STW: 90%, 90%; PET/CT-BW: 95%, 85%, PET/CT-STW: 95%, 86% and PET-only: 96%, 75%, respectively. CT-BW demonstrated higher specificity than PET-only and PET/CT-BW (p=0.0005 and p=0.0103, respectively) and trended toward higher sensitivity than CT-STW (p=0.0759). Malignant primary bone tumors were more avid than benign lesions overall (p<0.0001) but the avidity of benign aggressive lesions (giant cell tumors and Langerhans Cell Histiocytosis) trended higher than the malignancies (p=0.08). Conclusion. Bone windows provided high specificity for distinguishing between malignant and benign primary bone tumors and are recommended when viewing FDG PET/CT.

  5. 68Gallium-DOTATATE PET/CT Scanning Results in Patients with MEN1

    PubMed Central

    Sadowski, Samira M; Millo, Corina; Cottle-Delisle, Candice; Merkel, Roxanne; Yang, Lily A; Herscovitch, Peter; Pacak, Karel; Simonds, William F; Marx, Stephen J; Kebebew, Electron

    2015-01-01

    Background Screening for neuroendocrine tumors (NETs) in patients with multiple endocrine neoplasia type 1 (MEN1) is recommended to detect primary and metastatic tumors, which can result in significant morbidity and mortality. The utility of somatostatin receptor imaging 68Gallium-DOTATATE PET/CT in patients with MEN1 is not known. The aim of this study was to prospectively determine the accuracy of 68Gallium-DOTATATE PET/CT versus 111In-pentetreotide SPECT/CT and anatomic imaging in patients with MEN1. Study design Prospective study comparing 68Gallium-DOTATATE PET/CT, 111In-pentetreotide SPECT/CT, and triphasic CT scan to clinical, biochemical and pathological data in 26 patients with MEN1. Results 68Gallium-DOTATATE PET/CT detected 107 lesions; 111In- pentetreotide SPECT/CT detected 33 lesions; and CT scan detected 48 lesions. Lesions detected on 68Gallium-DOTATATE PET/CT had high SUVmax (median SUVmax = 72.8 [range 19–191]). In 7 of the 26 patients (27%), 68Gallium-DOTATATE PET/CT was positive with a negative 111In-pentetreotide SPECT/CT, and in 10 patients (38.5%), additional metastases were detected (range 0.3 cm to 1.5 cm). In 8 of the 26 patients (31%), there was a change in management recommendations as a result of the findings on 68Gallium-DOTATATE PET/CT that were not seen on 111In- pentetreotide SPECT/CT and CT scan. Conclusions 68Gallium-DOTATATE PET/CT is more sensitive for detecting NETs than 111In-pentetreotide SPECT/CT and CT scan in patients with MEN1. This imaging technique should be integrated into radiologic screening and surveillance of patients with MEN1, as it can significantly alter management recommendations. PMID:26206648

  6. Training of staff for the delivery of PET/CT services in the UK.

    PubMed

    Perkins, Alan C; Gordon, Isky; Read, James; Ellis, Beverly; Allen, R; Clarke, S E M; Garner, C; Hilson, A J; Frank, J W; McCool, D; Nicol, A; Prescott, M C; Ryan, P J; Shields, R A; Tindale, W B

    2006-12-01

    Evidence for the cost effectiveness of PET/CT imaging is now driving the widespread introduction of PET/CT services throughout the UK. The provision of PET/CT facilities will require a workforce of medical, scientific, technical and engineering staff who are adequately trained and fit for purpose. Suitably trained staff in this speciality are scarce. The development and accreditation of training courses and other educational resources for training programmes in all disciplines will therefore be required at a national and regional level. The implementation of PET/CT training can be achieved more cost-effectively by developing multi-professional learning resources whenever possible. It is intended that the recommendations would be implemented by close co-operation of both public and private healthcare providers together with educational establishments.

  7. 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

  8. Clinical utility of (18)F-fluoride PET/CT in benign and malignant bone diseases.

    PubMed

    Li, Yuxin; Schiepers, Christiaan; Lake, Ralph; Dadparvar, Simin; Berenji, Gholam R

    2012-01-01

    (18)F labeled sodium fluoride is a positron-emitting, bone seeking agent with more favorable skeletal kinetics than conventional phosphate and diphosphonate compounds. With the expanding clinical usage of PET/CT, there is renewed interest in using (18)F-fluoride PET/CT for imaging bone diseases. Growing evidence indicates that (18)F fluoride PET/CT offers increased sensitivity, specificity, and diagnostic accuracy in evaluating metastatic bone disease compared to (99m)Tc based bone scintigraphy. National Oncologic PET Registry (NOPR) has expanded coverage for (18)F sodium fluoride PET scans since February 2011 for the evaluation of osseous metastatic disease. In this article, we reviewed the pharmacological characteristics of sodium fluoride, as well as the clinical utility of PET/CT using (18)F-fluoride in both benign and malignant bone disorders.

  9. Unusual Horner's Syndrome in Recurrent Breast Cancer: Evaluation Using (18)F-FDG PET/CT.

    PubMed

    Park, Sohyun; Kim, Tae Sung; Kim, Seok-Ki

    2017-03-01

    (18)F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) is a widely used imaging modality in the initial diagnosis of cancer, treatment response evaluation and detection of recurrence. Herein, we present the case of a 39-year-old female who presented right ptosis on the follow-up of breast cancer after surgery. Clinicians suspected Horner's syndrome, and the patient underwent FDG PET/CT for the evaluation of recurrence that could cause Horner's syndrome. FDG PET/CT demonstrated a focal hypermetabolic lesion in the right cervicothoracic junction area, corresponding to the preganglionic cervical sympathetic trunk. A subsequent needle biopsy was done, and the lesion was confirmed as metastatic ductal carcinoma. In this case, we could detect the exact location of the recurring lesion that caused Horner's syndrome using FDG PET/CT.

  10. PET/CT-guided Interventions: Personnel Radiation Dose

    SciTech Connect

    Ryan, E. Ronan Thornton, Raymond; Sofocleous, Constantinos T.; Erinjeri, Joseph P.; Hsu, Meier; Quinn, Brian; Dauer, Lawrence T.; Solomon, Stephen B.

    2013-08-01

    PurposeTo quantify radiation exposure to the primary operator and staff during PET/CT-guided interventional procedures.MethodsIn this prospective study, 12 patients underwent PET/CT-guided interventions over a 6 month period. Radiation exposure was measured for the primary operator, the radiology technologist, and the nurse anesthetist by means of optically stimulated luminescence dosimeters. Radiation exposure was correlated with the procedure time and the use of in-room image guidance (CT fluoroscopy or ultrasound).ResultsThe median effective dose was 0.02 (range 0-0.13) mSv for the primary operator, 0.01 (range 0-0.05) mSv for the nurse anesthetist, and 0.02 (range 0-0.05) mSv for the radiology technologist. The median extremity dose equivalent for the operator was 0.05 (range 0-0.62) mSv. Radiation exposure correlated with procedure duration and with the use of in-room image guidance. The median operator effective dose for the procedure was 0.015 mSv when conventional biopsy mode CT was used, compared to 0.06 mSv for in-room image guidance, although this did not achieve statistical significance as a result of the small sample size (p = 0.06).ConclusionThe operator dose from PET/CT-guided procedures is not significantly different than typical doses from fluoroscopically guided procedures. The major determinant of radiation exposure to the operator from PET/CT-guided interventional procedures is time spent in close proximity to the patient.

  11. First-In-Human Study Demonstrating Tumor-Angiogenesis by PET/CT Imaging with 68Ga-NODAGA-THERANOST, a High-Affinity Peptidomimetic for αvβ3 Integrin Receptor Targeting

    PubMed Central

    Baum, Richard P.; Kulkarni, Harshad R.; Müller, Dirk; Danthi, Narasimhan; Kim, Young-Seung; Brechbiel, Martin W.

    2015-01-01

    Abstract 68Ga-NODAGA-THERANOST™ is an αvβ3 integrin antagonist and the first radiolabeled peptidomimetic to reach clinical development for targeting integrin receptors. In this first-in-human study, the feasibility of integrin receptor peptidomimetic positron emission tomography/computed tomography (PET/CT) imaging was confirmed in patients with non-small-cell lung cancer and breast cancer. Methods: Patients underwent PET/CT imaging with 68Ga NODAGA-THERANOST. PET images were analyzed qualitatively and quantitatively and compared to 2-deoxy-2-(18F) fluoro-d-glucose (18F-FDG) findings. Images were obtained 60 minutes postinjection of 300–500 MBq of 68Ga-NODAGA-THERANOST. Results: 68Ga-NODAGA-THERANOST revealed high tumor-to-background ratios (SUVmax=4.8) and uptake at neoangiogenesis sites. Reconstructed fused images distinguished cancers with high malignancy potential and enabled enhanced bone metastasis detection. 18F-FDG-positive lung and lymph node metastases did not show uptake, indicating the absence of neovascularization. Conclusions: 68Ga-NODAGA-THERANOST was found to be safe and effective, exhibiting in this study rapid blood clearance, stability, rapid renal excretion, favorable biodistribution and PK/PD, low irradiation burden (μSv/MBq/μg), and convenient radiolabeling. This radioligand might enable theranostics, that is, a combination of diagnostics followed by the appropriate therapeutics, namely antiangiogenic therapy, image-guided presurgical assessment, treatment response evaluation, prediction of pathologic response, neoadjuvant-peptidomimetic-radiochemotherapy, and personalized medicine strategies. Further clinical trials evaluating 68Ga-NODAGA-THERANOST are warranted. PMID:25945808

  12. Uterine Epithelioid Angiosarcoma on F-18 FDG PET/CT.

    PubMed

    Hwang, Jae Pil; Lim, Sang Moo

    2013-06-01

    Uterine epithelioid angiosarcoma can have conventional imaging characteristics similar to those of other uterine tumors, such as leiomyoma, leiomyosarcomas or hemangioendothelioma. Uterine epithelioid angiosarcoma exhibiting increased fluorine-18 fluorodeoxyglucose (F-18 FDG) activity can be misdiagnosed. A 61-year-old woman who was diagnosed with uterine epithelioid angiosarcoma underwent F-18 FDG positron emission tomography/computed tomography (PET/CT) as a part of the pretreatment work up for surgery. F-18 FDG PET/CT showed an intense F-18 FDG uptake in the uterus in addition to increased F-18 FDG uptake at the paraaortic and aortocaval lymph nodes. To our knowledge, this is the first case report of intense F-18 FDG uptake in uterine epithelioid angiosarcoma in Korea.

  13. PET/CT detects abdominal wall and port site metastases of colorectal carcinoma.

    PubMed

    Goshen, E; Davidson, T; Aderka, D; Zwas, S T

    2006-07-01

    Abdominal wall metastases from colorectal cancer (CRC) may be resected with curative results. Such lesions, often indicators of additional intra-abdominal lesions, may appear in surgical scars, stomas and port site metastases after laparoscope-assisted surgery (LAS). Post-operative changes, primarily surgical scars, alter local physical findings making early detection of small lesions challenging. The purpose of this study was to retrospectively evaluate the contribution of PET/CT to the diagnosis of recurrent colorectal cancer in the post-operative abdominal wall. 120 patients were referred for PET/CT with suspected recurrent CRC based on clinical, radiological or laboratory findings. All underwent whole body PET/CT imaging. 12 of these 120 (10%), were found to have abdominal wall lesions. A total of 16 abdominal wall lesions were detected, located to surgical scars, stomas, drain and laparoscope ports. Additional findings on PET/CT in this group included liver metastases, intra-abdominal lesions and retroperitoneal lymph node involvement. In general, the patients in this small group were young with high grade tumours presenting in advanced stages. In conclusion, PET/CT appears to be a sensitive tool for the diagnosis of abdominal wall recurrence of CRC. The accuracy of localization afforded by the fused functional and anatomic images makes PET/CT a likely tool for diagnosing abdominal wall lesions, including port site metastases of other aetiologies.

  14. Extensive invasive extramammary Paget disease evaluated by F-18 FDG PET/CT: a case report.

    PubMed

    Li, Zu-Gui; Qin, Xiao-Jing

    2015-01-01

    Extramammary Paget disease (EMPD) is a rare cutaneous, intraepithelial adenocarcinoma. Because of its rarity, little is known about the value of fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in evaluating this disease. Our case report aims to increase current knowledge of FDG PET/CT in EMPD as a noninvasive imaging tool for assessing the extension of the disease and detecting distant metastases.We reported a 64-year-old Chinese man who presented with a slowly progressive, ill-margined erythematous lesion with a crusted, eroded, and scaly surface involving multiple sites of penis, scrotum, left pelvic wall, hip, groin, and thigh for >4 years, which became extensive in the past 1 year. He was referred for an FDG PET/CT examination to further evaluate the lesions. A following skin biopsy was performed to obtain a definitive histological diagnosis.FDG PET/CT imaging revealed mild FDG uptake at the extensive cutaneous lesion with subcutaneous invasion, involvement of lymph nodes, and multiple intense FDG-avid of skeletal metastases. According to the appearance of FDG PET/CT, a provisional diagnosis of advanced cutaneous malignancy was made. Histopathology findings indicated characteristic of EMPD. The patient was treated with radiation therapy and died from complications 2 months after the last dose of radiotherapy.Our case highlighted that a whole-body FDG PET/CT should be incorporated into the diagnostic algorithm of EMPD to give a comprehensive assessment of this disease.

  15. Clinical utility of multimodality imaging with dynamic contrast-enhanced MRI, diffusion-weighted MRI, and 18F-FDG PET/CT for the prediction of neck control in oropharyngeal or hypopharyngeal squamous cell carcinoma treated with chemoradiation.

    PubMed

    Ng, Shu-Hang; Lin, Chien-Yu; Chan, Sheng-Chieh; Lin, Yu-Chun; Yen, Tzu-Chen; Liao, Chun-Ta; Chang, Joseph Tung-Chieh; Ko, Sheung-Fat; Wang, Hung-Ming; Chang, Chee-Jen; Wang, Jiun-Jie

    2014-01-01

    The clinical usefulness of pretreatment imaging techniques for predicting neck control in patients with oropharyngeal or hypopharyngeal squamous cell carcinoma (OHSCC) treated with chemoradiation remains unclear. In this prospective study, we investigated the role of pretreatment dynamic contrast-enhanced perfusion MR imaging (DCE-PWI), diffusion-weighted MR imaging (DWI), and [18F]fluorodeoxyglucose-positron emission tomography (18F-FDG PET)/CT derived imaging markers for the prediction of neck control in OHSCC patients treated with chemoradiation. Patients with untreated OHSCC scheduled for chemoradiation between August, 2010 and July, 2012 were eligible for the study. Clinical variables and the following imaging parameters of metastatic neck lymph nodes were examined in relation to neck control: transfer constant, volume of blood plasma, and volume of extracellular extravascular space (Ve) on DCE-PWI; apparent diffusion coefficient (ADC) on DWI; maximum standardized uptake value, metabolic tumor volume, and total lesion glycolysis on 18F-FDG PET/CT. There were 69 patients (37 with oropharynx SCC and 32 with hypopharynx SCC) with successful pretreatment DCE-PWI and DWI available for analysis. After a median follow-up of 31 months, 25 (36.2%) participants had neck failure. Multivariate analysis identified hemoglobin level <14.3 g/dL (P = 0.019), Ve <0.23 (P = 0.040), and ADC >1.14×10-3 mm2/s (P = 0.003) as independent prognostic factors for 3-year neck control. A prognostic scoring system was formulated by summing up the three significant predictors of neck control. Patients with scores of 2-3 had significantly poorer neck control and overall survival rates than patients with scores of 0-1. We conclude that hemoglobin levels, Ve, and ADC are independent pretreatment prognostic factors for neck control in OHSCC treated with chemoradiation. Their combination may identify a subgroup of patients at high risk of developing neck failure.

  16. Multimodality functional imaging using DW-MRI and 18F-FDG-PET/CT during radiation therapy for human papillomavirus negative head and neck squamous cell carcinoma: Meixoeiro Hospital of Vigo Experience

    PubMed Central

    Aramburu Núñez, David; Lopez Medina, Antonio; Mera Iglesias, Moisés; Salvador Gomez, Francisco; Dave, Abhay; Hatzoglou, Vaios; Paudyal, Ramesh; Calzado, Alfonso; Deasy, Joseph O; Shukla-Dave, Amita; Muñoz, Victor M

    2017-01-01

    AIM To noninvasively investigate tumor cellularity measured using diffusion-weighted magnetic resonance imaging (DW-MRI) and glucose metabolism measured by 18F-labeled fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) during radiation therapy (RT) for human papillomavirus negative (HPV-) head and neck squamous cell carcinoma (HNSCC). METHODS In this prospective study, 6 HPV- HNSCC patients underwent a total of 34 multimodality imaging examinations DW-MRI at 1.5 T Philips MRI scanner [(n = 24) pre-, during- (2-3 wk), and post-treatment (Tx), and 18F-FDG PET/CT pre- and post-Tx (n = 10)]. All patients received RT. Monoexponential modeling of the DW-MRI data yielded the imaging metric apparent diffusion coefficient (ADC) and the mean of standardized uptake value (SUV) was measured from 18F-FDG PET uptake. All patients had a clinical follow-up as the standard of care and survival status was documented at 1 year. RESULTS There was a strong negative correlation between the mean of pretreatment ADC (ρ = -0.67, P = 0.01) and the pretreatment 18F-FDG PET SUV. The percentage (%) change in delta (∆) ADC for primary tumors and neck nodal metastases between pre- and Wk2-3 Tx were as follows: 75.4% and 61.6%, respectively, for the patient with no evidence of disease, 27.5% and 32.7%, respectively, for those patients who were alive with disease, and 26.9% and 7.31%, respectively, for those who were dead with disease. CONCLUSION These results are preliminary in nature and are indicative, and not definitive, trends rendered by the imaging metrics due to the small sample size of HPV- HNSCC patients in a Meixoeiro Hospital of Vigo Experience. PMID:28144403

  17. Diffuse Large B-Cell Lymphoma: Prospective Multicenter Comparison of Early Interim FLT PET/CT versus FDG PET/CT with IHP, EORTC, Deauville, and PERCIST Criteria for Early Therapeutic Monitoring.

    PubMed

    Minamimoto, Ryogo; Fayad, Luis; Advani, Ranjana; Vose, Julie; Macapinlac, Homer; Meza, Jane; Hankins, Jordan; Mottaghy, Felix; Juweid, Malik; Quon, Andrew

    2016-07-01

    Purpose To compare the performance characteristics of interim fluorine 18 ((18)F) fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) (after two cycles of chemotherapy) by using the most prominent standardized interpretive criteria (including International Harmonization Project [IHP] criteria, European Organization for Research and Treatment of Cancer [EORTC] criteria, and PET Response Criteria in Solid Tumors (PERCIST) versus those of interim (18)F fluorothymidine (FLT) PET/CT and simple visual interpretation. Materials and Methods This HIPAA-compliant prospective study was approved by the institutional review boards, and written informed consent was obtained. Patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL) underwent both FLT and FDG PET/CT 18-24 days after two cycles of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone or rituximab, etoposide, prednisone, vincristine, cyclophosphamide, and doxorubicin. For FDG PET/CT interpretation, IHP criteria, EORTC criteria, PERCIST, Deauville criteria, standardized uptake value, total lesion glycolysis, and metabolic tumor volume were used. FLT PET/CT images were interpreted with visual assessment by two reviewers in consensus. The interim (after cycle 2) FDG and FLT PET/CT studies were then compared with the end-of-treatment FDG PET/CT studies to determine which interim examination and/or criteria best predicted the result after six cycles of chemotherapy. Results From November 2011 to May 2014, there were 60 potential patients for inclusion, of whom 46 patients (24 men [mean age, 60.9 years ± 13.7; range, 28-78 years] and 22 women [mean age, 57.2 years ± 13.4; range, 25-76 years]) fulfilled the criteria. Thirty-four patients had complete response, and 12 had residual disease at the end of treatment. FLT PET/CT had a significantly higher positive predictive value (PPV) (91%) in predicting residual disease than did any FDG PET/CT interpretation method

  18. The role of PET-CT in radiotherapy planning of solid tumours

    PubMed Central

    Jelercic, Stasa; Rajer, Mirjana

    2015-01-01

    Background PET-CT is becoming more and more important in various aspects of oncology. Until recently it was used mainly as part of diagnostic procedures and for evaluation of treatment results. With development of personalized radiotherapy, volumetric and radiobiological characteristics of individual tumour have become integrated in the multistep radiotherapy (RT) planning process. Standard anatomical imaging used to select and delineate RT target volumes can be enriched by the information on tumour biology gained by PET-CT. In this review we explore the current and possible future role of PET-CT in radiotherapy treatment planning. After general explanation, we assess its role in radiotherapy of those solid tumours for which PET-CT is being used most. Conclusions In the nearby future PET-CT will be an integral part of the most radiotherapy treatment planning procedures in an every-day clinical practice. Apart from a clear role in radiation planning of lung cancer, with forthcoming clinical trials, we will get more evidence of the optimal use of PET-CT in radiotherapy planning of other solid tumours. PMID:25810695

  19. 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.

  20. Volume-Based F-18 FDG PET/CT Imaging Markers Provide Supplemental Prognostic Information to Histologic Grading in Patients With High-Grade Bone or Soft Tissue Sarcoma.

    PubMed

    Andersen, Kim Francis; Fuglo, Hanna Maria; Rasmussen, Sine Hvid; Petersen, Michael Mork; Loft, Annika

    2015-12-01

    The aim of the study is to assess the prognostic value of different volume-based calculations of tumor metabolic activity in the initial assessment of patients with high-grade bone sarcomas (BS) and soft tissue sarcomas (STS) using F-18 FDG PET/CT.A single-site, retrospective study from 2002 to 2012 including 92 patients with histologically verified high-grade BS (N = 37) or STS (N = 55). All patients underwent a pretreatment F-18 FDG PET/CT scan. Clinical data were registered. Measurements of the accuracy of metabolic tumor volume with a preset threshold of 40% of the maximum standardized uptake value of primary tumor (MTV40%) and total lesion glycolysis (TLG) as prognostic variables and identification of optimal discriminating cut-off values were performed through ROC curve analysis. Patients were grouped according to the cut-off values. All deaths were considered an event in survival analysis. Kaplan-Meier survival estimates and log-rank test were used to compare the degree of equality of survival distributions. Prognostic variables with related hazard ratios (HR) were assessed using Cox proportional hazards regression analysis.Forty-one of 92 patients died during follow-up (45%; 12 BS and 29 STS). Average survival for included patients was 6.5 years (95% CI 5.8-7.3 years) and probability of 5-year survival was 52%. There was a high-significant accuracy of TLG and MTV40% as prognostic variables when looking on all patients and during subgroup analysis. AUCs were higher for TLG than for MTV40%. TLG above optimal cut-off value was the only variable which was independently prognostic for survival throughout multivariate regression analysis of all included patients (P = 0.01, HR 4.78 [95% CI 1.45-15.87]) and subgroup analysis (BS: P = 0.04, HR 11.11 [95% CI 1.09-111.11]; STS: P < 0.05, HR 3.37 [95% CI 1.02-11.11]). No significant results were demonstrated for MTV40%.Volume-based F-18 FDG PET/CT imaging markers in terms of pretreatment estimation

  1. (18)F-FLT and (18)F-FDG PET-CT imaging in the evaluation of early therapeutic effects of chemotherapy on Walker 256 tumor-bearing rats.

    PubMed

    Xu, Weina; Yu, Shupeng; Xin, Jun; Guo, Qiyong

    2016-12-01

    The present study aimed to evaluate the early therapeutic effects of chemotherapy on Walker 256 tumor-bearing Wistar rats via F-18-fluoro-3'-deoxy-3'-L-fluorothymidine ((18)F-FLT) and F-18-fluoro-deoxyglucose ((18)F-FDG) positron emission tomography-computed tomography (PET-CT) imaging. Walker 256 tumor-bearing Wistar rats were subjected to (18)F-FLT and (18)F-FDG PET-CT imaging prior to and 24 and 48 h after epirubicin chemotherapy. (18)F-FLT and (18)F-FDG uptake [tumor/muscle (T/M)], the percentage of injected dose per gram (% ID/g), and the Ki-67 labeling index (LI-Ki-67) were quantitatively determined for each rat prior to and following epirubicin chemotherapy. The correlation between % ID/g and tumor LI-Ki-67 was analyzed. Both (18)F-FLT and (18)F-FDG tumor uptake decreased significantly at 24 and 48 h after chemotherapy (P<0.01 and P<0.05, respectively). LI-Ki-67 also significantly reduced 24 and 48 h after chemotherapy (P<0.001). Furthermore, (18)F-FLT and (18)F-FDG T/M tumor uptake correlated positively with LI-Ki-67 before and after chemotherapy (r=0.842 and 0.813, respectively). During the early post-chemotherapy stage, (18)F-FLT and (18)F-FDG uptake in Walker 256 tumors reduced significantly, which correlated positively with the tumor cell proliferative activity.

  2. 18F-FLT and 18F-FDG PET-CT imaging in the evaluation of early therapeutic effects of chemotherapy on Walker 256 tumor-bearing rats

    PubMed Central

    Xu, Weina; Yu, Shupeng; Xin, Jun; Guo, Qiyong

    2016-01-01

    The present study aimed to evaluate the early therapeutic effects of chemotherapy on Walker 256 tumor-bearing Wistar rats via F-18-fluoro-3′-deoxy-3′-L-fluorothymidine (18F-FLT) and F-18-fluoro-deoxyglucose (18F-FDG) positron emission tomography-computed tomography (PET-CT) imaging. Walker 256 tumor-bearing Wistar rats were subjected to 18F-FLT and 18F-FDG PET-CT imaging prior to and 24 and 48 h after epirubicin chemotherapy. 18F-FLT and 18F-FDG uptake [tumor/muscle (T/M)], the percentage of injected dose per gram (% ID/g), and the Ki-67 labeling index (LI-Ki-67) were quantitatively determined for each rat prior to and following epirubicin chemotherapy. The correlation between % ID/g and tumor LI-Ki-67 was analyzed. Both 18F-FLT and 18F-FDG tumor uptake decreased significantly at 24 and 48 h after chemotherapy (P<0.01 and P<0.05, respectively). LI-Ki-67 also significantly reduced 24 and 48 h after chemotherapy (P<0.001). Furthermore, 18F-FLT and 18F-FDG T/M tumor uptake correlated positively with LI-Ki-67 before and after chemotherapy (r=0.842 and 0.813, respectively). During the early post-chemotherapy stage, 18F-FLT and 18F-FDG uptake in Walker 256 tumors reduced significantly, which correlated positively with the tumor cell proliferative activity. PMID:28101193

  3. PET/CT fusion viewing software for use with picture archiving and communication systems.

    PubMed

    Im, Ki Chun; Choi, Ik Soo; Ryu, Jin-Sook; Eo, Gi Seoung; Kim, Jae Seung; Moon, Dae Hyuk

    2010-12-01

    We developed positron emission tomography (PET)/computed tomography (CT) viewing software (PETviewer) that can display co-registered PET and CT images obtained by PET/CT and stored on picture archiving and communication systems (PACS). PETviewer has tools for presetting windows for CT display; control bars for PET window level; zoom, pan, and pseudo-color functions; and allows the user to draw a rectangular region of interest (ROI) for standardized uptake value (SUV) measurement. SUV was calculated using PET DICOM header information and the pixel intensity in PETviewer. Reconstructed datasets of PET/CT and maximum intensity projection (MIP) of the PET images were transferred and archived in PACS. Phantom experiments were performed to evaluate the validity of image fusion. PET/CT images were displayed on an independent window in PACS. Transaxial PET images were reformatted as sagittal and coronal PET images, which were displayed with the corresponding CT and PET/CT fusion images with adjustable color and transparency. Transaxial, sagittal, and coronal PET images corresponding to the location of the cursor were shown using cine display of MIP images. All images were displayed in PETviewer within 20 s on a personal computer for PACS, which was equipped with a P4, 1.3-GHz CPU, and 512 Mb of RAM. We could measure maximum and mean SUV in a ROI using PETviewer. Transaxial fused images of patients and phantoms showed excellent registration and fusion of PET and CT images in the X and Y directions. PETviewer provided very useful clinical tools for assessing PET/CT images on PACS and should assist in maximizing the benefits derived from PET/CT imaging.

  4. Safety and Efficacy of 68Ga-DOTATATE PET/CT for Diagnosis, Staging, and Treatment Management of Neuroendocrine Tumors

    PubMed Central

    Deppen, Stephen A.; Liu, Eric; Blume, Jeffrey D.; Clanton, Jeffrey; Shi, Chanjuan; Jones-Jackson, Laurie B.; Lakhani, Vipul; Baum, Richard P.; Berlin, Jordan; Smith, Gary T.; Graham, Michael; Sandler, Martin P.; Delbeke, Dominique; Walker, Ronald C.

    2017-01-01

    Our purpose was to evaluate safety and efficacy of 68Ga-DOTATATE PET/CT compared with 111In-pentetreotide imaging for diagnosis, staging, and restaging of pulmonary and gastroenteropancreatic neuroendocrine tumors. Methods 68Ga-DOTATATE PET/CT and 111In-pentetreotide scans were obtained for 78 of 97 consecutively enrolled patients with known or suspected pulmonary or gastroenteropancreatic neuroendocrine tumors. Safety and toxicity were measured by comparing vital signs, serum chemistry values, or acquisition-related medical complications before and after 68Ga-DOTATATE injection. Added value was determined by changes in treatment plan when 68Ga-DOTATATE PET/CT results were added to all prior imaging, including 111In-pentetreotide. Interobserver reproducibility of 68Ga-DOTATATE PET/CT scan interpretation was measured between blinded and nonblinded interpreters. Results 68Ga-DOTATATE PET/CT and 111In-pentetreotide scans were significantly different in impact on treatment (P < 0.001). 68Ga-DOTATATE PET/CT combined with CT or liver MRI changed care in 28 of 78 (36%) patients. Interobserver agreement between blinded and nonblinded interpreters was high. No participant had a trial-related event requiring treatment. Mild, transient events were tachycardia in 1, alanine transaminase elevation in 1, and hyperglycemia in 2 participants. No clinically significant arrhythmias occurred. 68Ga-DOTATATE PET/CT correctly identified 3 patients for peptide-receptor radiotherapy incorrectly classified by 111In-pentetreotide. Conclusion 68Ga-DOTATATE PET/CT was equivalent or superior to 111In-pentetreotide imaging in all 78 patients. No adverse events requiring treatment were observed. 68Ga-DOTATATE PET/CT changed treatment in 36% of participants. Given the lack of significant toxicity, lower radiation exposure, and improved accuracy compared with 111In-pentetreotide, 68Ga-DOTATATE imaging should be used instead of 111In-pentetreotide imaging where available. PMID:26769865

  5. Multimodal target correction by local bone registration: a PET/CT evaluation.

    PubMed

    Oliveira-Santos, Thiago; Weitzel, Thilo; Klaeser, Bernd; Krause, Thomas; Nolte, Lutz-Peter; Weber, Stefan; Reyes, Mauricio

    2010-01-01

    PET/CT guidance for percutaneous interventions allows biopsy of suspicious metabolically active bone lesions even when no morphological correlation is delineable in the CT images. Clinical use of PET/CT guidance with conventional step-by-step technique is time consuming and complicated especially in cases in which the target lesion is not shown in the CT image. Our recently developed multimodal instrument guidance system (IGS) for PET/CT improved this situation. Nevertheless, bone biopsies even with IGS have a trade-off between precision and intervention duration which is proportional to patient and personnel exposure to radiation. As image acquisition and reconstruction of PET may take up to 10 minutes, preferably only one time consuming combined PET/CT acquisition should be needed during an intervention. In case of required additional control images in order to check for possible patient movements/deformations, or to verify the final needle position in the target, only fast CT acquisitions should be performed. However, for precise instrument guidance accounting for patient movement and/or deformation without having a control PET image, it is essential to be able to transfer the position of the target as identified in the original PET/CT to a changed situation as shown in the control CT.

  6. Lymphoma and tuberculosis: temporal evolution of dual pathology on sequential 18F-FDG PET/CT.

    PubMed

    Mukherjee, Anirban; Sharma, Punit; Karunanithi, Sellam; Dhull, Varun Singh; Kumar, Rakesh

    2014-08-01

    Tuberculosis can often be seen in patients undergoing chemotherapy for lymphoma, especially in endemic countries. As both tuberculosis and lymphoma can lead to hypermetabolic lesions of F-FDG PET/CT, a diagnostic dilemma often ensues. We present the sequential F-FDG PET/CT images of a 22-year-old female patient with Hodgkin lymphoma who developed tuberculosis and later relapse of lymphoma. These images present the temporal evaluation of the dual pathology on F-FDG PET/CT.

  7. Prognostic Value of Quantitative Metabolic Metrics on Baseline Pre-Sunitinib FDG PET/CT in Advanced Renal Cell Carcinoma

    PubMed Central

    Minamimoto, Ryogo; Barkhodari, Amir; Harshman, Lauren; Srinivas, Sandy; Quon, Andrew

    2016-01-01

    Purpose The objective of this study was to prospectively evaluate various quantitative metrics on FDG PET/CT for monitoring sunitinib therapy and predicting prognosis in patients with metastatic renal cell cancer (mRCC). Methods Seventeen patients (mean age: 59.0 ± 11.6) prospectively underwent a baseline FDG PET/CT and interim PET/CT after 2 cycles (12 weeks) of sunitinib therapy. We measured the highest maximum standardized uptake value (SUVmax) of all identified lesions (highest SUVmax), sum of SUVmax with maximum six lesions (sum of SUVmax), total lesion glycolysis (TLG) and metabolic tumor volume (MTV) from baseline PET/CT and interim PET/CT, and the % decrease in highest SUVmax of lesion (%Δ highest SUVmax), the % decrease in sum of SUVmax, the % decrease in TLG (%ΔTLG) and the % decrease in MTV (%ΔMTV) between baseline and interim PET/CT, and the imaging results were validated by clinical follow-up at 12 months after completion of therapy for progression free survival (PFS). Results At 12 month follow-up, 6/17 (35.3%) patients achieved PFS, while 11/17 (64.7%) patients were deemed to have progression of disease or recurrence within the previous 12 months. At baseline, PET/CT demonstrated metabolically active cancer in all cases. Using baseline PET/CT alone, all of the quantitative imaging metrics were predictive of PFS. Using interim PET/CT, the %Δ highest SUVmax, %Δ sum of SUVmax, and %ΔTLG were also predictive of PFS. Otherwise, interim PET/CT showed no significant difference between the two survival groups regardless of the quantitative metric utilized including MTV and TLG. Conclusions Quantitative metabolic measurements on baseline PET/CT appears to be predictive of PFS at 12 months post-therapy in patients scheduled to undergo sunitinib therapy for mRCC. Change between baseline and interim PET/CT also appeared to have prognostic value but otherwise interim PET/CT after 12 weeks of sunitinib did not appear to be predictive of PFS. PMID:27123976

  8. Hybrid registration of PET/CT in thoracic region with pre-filtering PET sinogram

    NASA Astrophysics Data System (ADS)

    Mokri, S. S.; Saripan, M. I.; Marhaban, M. H.; Nordin, A. J.; Hashim, S.

    2015-11-01

    The integration of physiological (PET) and anatomical (CT) images in cancer delineation requires an accurate spatial registration technique. Although hybrid PET/CT scanner is used to co-register these images, significant misregistrations exist due to patient and respiratory/cardiac motions. This paper proposes a hybrid feature-intensity based registration technique for hybrid PET/CT scanner. First, simulated PET sinogram was filtered with a 3D hybrid mean-median before reconstructing the image. The features were then derived from the segmented structures (lung, heart and tumor) from both images. The registration was performed based on modified multi-modality demon registration with multiresolution scheme. Apart from visual observations improvements, the proposed registration technique increased the normalized mutual information index (NMI) between the PET/CT images after registration. All nine tested datasets show marked improvements in mutual information (MI) index than free form deformation (FFD) registration technique with the highest MI increase is 25%.

  9. Evaluation of Prostate Cancer with 11C- and 18F-Choline PET/CT: Diagnosis and Initial Staging.

    PubMed

    Nitsch, Sascha; Hakenberg, Oliver W; Heuschkel, Martin; Dräger, Desiree; Hildebrandt, Guido; Krause, Bernd J; Schwarzenböck, Sarah M

    2016-10-01

    Early diagnosis and adequate staging are crucial for the choice of adequate treatment in prostate cancer (PC). Morphologic and functional imaging modalities, such as CT and MRI, have had limited accuracy in the diagnosis and nodal staging of PC. Molecular PET/CT imaging with (11)C- or (18)F-choline-labeled derivatives is increasingly being used, but its role in the diagnosis and initial staging of PC is controversial because of limitations in sensitivity and specificity for the detection of primary PC. For T staging, functional MRI is superior to (11)C- or (18)F-choline PET/CT. For N staging, (11)C- or (18)F-choline PET/CT can provide potentially useful information that may influence treatment planning. For the detection of bone metastases, (11)C- or (18)F-choline PET/CT has had promising results; however, in terms of cost-effectiveness, the routine use of (11)C- or (18)F-choline PET/CT is still debatable. (11)C- or (18)F-choline PET/CT might be used in high-risk PC before radiation treatment planning, potentially affecting this planning (e.g., regarding dose escalation). This review provides an overview of the diagnostic accuracy and limitations of (11)C- or (18)F-choline PET/CT in the diagnosis and staging of PC.

  10. F-18 fluorodeoxyglucose PET/CT and post hoc PET/MRI in a case of primary meningeal melanomatosis.

    PubMed

    Lee, Hong Je; Ahn, Byeong-Cheol; Hwang, Seong Wook; Cho, Suk Kyong; Kim, Hae Won; Lee, Sang-Woo; Hwang, Jeong-Hyun; Lee, Jaetae

    2013-01-01

    Primary meningeal melanomatosis is a rare, aggressive variant of primary malignant melanoma of the central nervous system, which arises from melanocytes within the leptomeninges and carries a poor prognosis. We report a case of primary meningeal melanomatosis in a 17-year-old man, which was diagnosed with (18)F-fluorodeoxyglucose (F-18 FDG) PET/CT, and post hoc F-18 FDG PET/MRI fusion images. Whole-body F-18 FDG PET/CT was helpful in ruling out the extracranial origin of melanoma lesions, and in assessing the therapeutic response. Post hoc PET/MRI fusion images facilitated the correlation between PET and MRI images and demonstrated the hypermetabolic lesions more accurately than the unenhanced PET/CT images. Whole body F-18 FDG PET/CT and post hoc PET/MRI images might help clinicians determine the best therapeutic strategy for patients with primary meningeal melanomatosis.

  11. [PET/CT for diagnostics and therapy stratification of lung cancer].

    PubMed

    Kratochwil, C; Haberkorn, U; Giesel, F L

    2010-08-01

    With the introduction of positron emission tomography (PET) and more recently the hybrid systems PET/CT, the management of cancer patients in the treatment strategy has changed tremendously. The combination of PET with multidetector CT scanning enables the integration of metabolic and high resolution morphological image information. PET/CT is nowadays an established modality for tumor detection, characterization, staging and response monitoring. The increased installation of PET/CT systems worldwide and also the increased scientific publications underline the importance of this imaging modality. PET/CT is particular the imaging modality of choice in lung cancer staging and re-staging (T, N and M staging). The possible increased success of surgery in lung cancer patients and also the expected reduction in additional invasive diagnostics lead to benefits for both the individual patient and the healthcare system. In this review article PET and PET/CT is presented for diagnostic and therapeutic stratification in lung cancer. The fundamentals of glucose metabolism, staging, tumor recurrence and therapeutic monitoring are presented.

  12. 18F-FDG PET/CT in Neurolymphomatosis: Report of 3 Cases

    PubMed Central

    Canh, Nguyen Xuan; Tan, Ngo Van; Tung, Tran Thanh; Son, Nguyen Truong; Maurea, Simone

    2014-01-01

    Neurolymphomatosis is a rare manifestation of non-Hodgkin lymphoma characterized by infiltration of peripheral nerves, nerve roots, plexus and cranial nerves by malignant lymphocytes. This report presents positron emission tomography/computed tomography (PET/CT)imaging with 2-deoxy-2-18F-fluoro-D-glucose (18F-FDG) in 3 cases of non-Hodgkin lymphoma with nerve infiltration, including one newly diagnosed lymphoma, one recurrent lymphoma in previous nerve lesions and one newly recurrent lymphoma. PET/CT could reveal the affected neural structures including cranial nerves, spinal nerve roots, brachial plexus, cervicothoracic ganglion, intercostal nerves, branches of the vagus nerve, lumbosacral plexus and sciatic nerves. There was relative concordance between PET/CT and MRI in detection of affected cranial nerves. PET/CT seemed to be better than MRI in detection of affected peripheral nerves. 18F-FDG PET/CT was a whole-body imaging technique with the ability to reveal the affected cranial nerves, peripheral nerves, nerve roots and plexus in non-Hodgkin lymphoma. A thorough understanding of disease and use of advanced imaging modalities will increasingly detect neurolymphomatosis. PMID:27408859

  13. Detection of Internal Mammary Adenopathy in Patients With Breast Cancer by PET/CT and MRI

    PubMed Central

    Jochelson, Maxine S.; Lebron, Lizza; Jacobs, Stefanie S.; Zheng, Junting; Moskowitz, Chaya S.; Powell, Simon N.; Sacchini, Virgilio; Ulaner, Gary A.; Morris, Elizabeth A.; Dershaw, D. David

    2016-01-01

    OBJECTIVE The purpose of this study was to assess the prevalence of internal mammary node (IMN) adenopathy in patients with breast cancer and compare breast MRI and PET/CT for detection of IMN adenopathy. MATERIALS AND METHODS This retrospective study included 90 women who underwent MRI and PET/CT before neoadjuvant chemotherapy for clinical stage IIA through IIIA disease. MRI and PET/CT examinations were read independently by two readers trained in breast imaging and nuclear medicine. All patients underwent follow-up MRI at the end of chemotherapy, and 10 with hypermetabolic IMNs underwent follow-up PET/CT. Histology was not obtained. Women were considered to have IMN adenopathy when nodes seen on MRI or having standardized uptake value (SUV) greater than mediastinal blood pool decreased in either size or SUV (or both) after treatment. Features including lymphovascular invasion, tumor quadrant(s), and axillary adenopathy were compared between presence and absence of IMN adenopathy using Fisher’s exact test. Prevalence was determined on the basis of the percentage of patients with IMN adenopathy by either modality. The McNemar test compared the prevalence of IMN adenopathy on MRI to its prevalence on PET/CT. RESULTS Prevalence of IMN adenopathy was 16% (14/90) by MRI and 14% (13/90) by PET/CT (p = 0.317). After chemotherapy, IMN adenopathy resolved in 12 of 14 patients (86%). In two patients with poor responses in primary tumors, IMN adenopathy persisted, and both patients developed metastatic disease within 6 months. At 3 years, survival was significantly worse in patients with IMN adenopathy than in those without (85.7% vs 53.3%, respectively; p = 0.009). CONCLUSION In women with advanced breast cancer receiving neoadjuvant chemotherapy, prevalence of IMN adenopathy was 16%, equally detected by breast MRI and PET/CT. Identification of IMN adenopathy may affect treatment and provides prognostic information. PMID:26397342

  14. Corticosteroid Responsive Sarcoidosis with Multisystemic Involvement Years after Initial Diagnosis: A Lymphoma Mimicker on 18-FDG PET/CT

    PubMed Central

    Acar, Turker; Savas, Recep; Kocacelebi, Kenan; Ucan, Eyup Sabri

    2015-01-01

    Sarcoidosis is a chronic multisystemic inflammatory disease characterized by noncaseating epithelioid cell granulomas. 18-Fluorodeoxyglucose positron-emission tomography/computer tomography (FDG-PET/CT) is increasingly used in routine clinical practice to assess active sarcoidosis because it can detect active inflammatory granulomatous disease. However, active sarcoidosis lesions are observed to be hypermetabolic on FDG-PET/CT much like malignancies, which may lead to misinterpretation on imaging. In this case report, we present a rare case of sarcoidosis with multisystem involvement including lung, lymph nodes, bone, pleura, and soft tissue that mimicked lymphoma on FDG-PET/CT and responded to corticosteroid treatment. PMID:26312138

  15. Current concepts in F18 FDG PET/CT-based radiation therapy planning for lung cancer.

    PubMed

    Lee, Percy; Kupelian, Patrick; Czernin, Johannes; Ghosh, Partha

    2012-01-01

    Radiation therapy is an important component of cancer therapy for early stage as well as locally advanced lung cancer. The use of F18 FDG PET/CT has come to the forefront of lung cancer staging and overall treatment decision-making. FDG PET/CT parameters such as standard uptake value and metabolic tumor volume provide important prognostic and predictive information in lung cancer. Importantly, FDG PET/CT for radiation planning has added biological information in defining the gross tumor volume as well as involved nodal disease. For example, accurate target delineation between tumor and atelectasis is facilitated by utilizing PET and CT imaging. Furthermore, there has been meaningful progress in incorporating metabolic information from FDG PET/CT imaging in radiation treatment planning strategies such as radiation dose escalation based on standard uptake value thresholds as well as using respiratory-gated PET and CT planning for improved target delineation of moving targets. In addition, PET/CT-based follow-up after radiation therapy has provided the possibility of early detection of local as well as distant recurrences after treatment. More research is needed to incorporate other biomarkers such as proliferative and hypoxia biomarkers in PET as well as integrating metabolic information in adaptive, patient-centered, tailored radiation therapy.

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

    PubMed

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

    2017-02-08

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

  17. Usefulness of PET/CT in the diagnosis of recurrent or metastasized differentiated thyroid carcinoma

    PubMed Central

    LU, CUN-ZHI; CAO, SU-SHENG; WANG, WEI; LIU, JUN; FU, NING; LU, FENG

    2016-01-01

    The aim of the present study was to determine the usefulness of the positron emission tomography/computed tomography (PET/CT) with 18F-fluorodeoxyglucose (FDG) in the detection of recurrence or metastasization of differentiated thyroid carcinoma (DTC) in patients with abnormal thyroglobulin levels and negative findings on the 131I-diagnostic whole-body scanning (dWBS). Fifteen patients with DTC, abnormal thyroglobulin levels, and negative 131I-dWBS findings were scanned using the 18F-FDG PET/CT. Positive diagnosis was based on postoperative histologic findings, and clinical and imaging follow-up results obtained in the subsequent 6 months. In addition, preoperative and postoperative thyroglobulin levels were compared. Using the findings of 18F-FDG PET/CT and data on confirmed positive diagnosis, sensitivity and positive predictive value (PPV) were calculated. Sensitivity and PPV of PET/CT in detecting recurrence or metastasisization of DTC were 93.30 and 91.40%, respectively. Furthermore, postoperative thyroglobulin levels were markedly lower compared to the preoperative levels (respectively, 4.67±1.71 vs. 58.53±18.34 ng/ml; p<0.05). PET/CT scan with 18F-FDG is an informative technique for the detection of recurrent or metastasized DTC in patients with abnormal thyroglobulin levels and negative 131I-dWBS findings. PMID:27073490

  18. Monitoring the Therapy of Extensive Osseous Sarcoidosis With FDG PET/CT.

    PubMed

    Yang, Hua; Numani, Shah; Liu, Shuang

    2017-02-24

    FDG PET/CT was performed in a 47-year-old man to evaluate possible malignancy of the spine revealed by MRI. The PET images revealed numerous focal FDG activity throughout the skeletal system. In addition, multiple foci of the increased activity in the mediastinal and hilar nodes were noted, suggestive of sarcoidosis, which was proven following biopsy. Therapy for sarcoidosis was initiated. In the subsequent 4 follow-up FDG PET/CT scans, the activity in both the bones and mediastinal/hilar regions fluctuated. However, anatomical abnormality in the bones on the CT images was never visualized during the entire clinical course.

  19. 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.

  20. Sensitivity of Image Features to Noise in Conventional and Respiratory-Gated PET/CT Images of Lung Cancer: Uncorrelated Noise Effects.

    PubMed

    Oliver, Jasmine A; Budzevich, Mikalai; Hunt, Dylan; Moros, Eduardo G; Latifi, Kujtim; Dilling, Thomas J; Feygelman, Vladimir; Zhang, Geoffrey

    2016-08-08

    The effect of noise on image features has yet to be studied in depth. Our objective was to explore how significantly image features are affected by the addition of uncorrelated noise to an image. The signal-to-noise ratio and noise power spectrum were calculated for a positron emission tomography/computed tomography scanner using a Ge-68 phantom. The conventional and respiratory-gated positron emission tomography/computed tomography images of 31 patients with lung cancer were retrospectively examined. Multiple sets of noise images were created for each original image by adding Gaussian noise of varying standard deviation equal to 2.5%, 4.0%, and 6.0% of the maximum intensity for positron emission tomography images and 10, 20, 50, 80, and 120 Hounsfield units for computed tomography images. Image features were extracted from all images, and percentage differences between the original image and the noise image feature values were calculated. These features were then categorized according to the noise sensitivity. The contour-dependent shape descriptors averaged below 4% difference in positron emission tomography and below 13% difference in computed tomography between noise and original images. Gray level size zone matrix features were the most sensitive to uncorrelated noise exhibiting average differences >200% for conventional and respiratory-gated images in computed tomography and 90% in positron emission tomography. Image feature differences increased as the noise level increased for shape, intensity, and gray-level co-occurrence matrix features in positron emission tomography and for gray-level co-occurrence matrix and gray-level size zone matrix features in conventional computed tomography. Investigators should be aware of the noise effects on image features.

  1. PET/CT in giant cell arteritis: High (18)F-FDG uptake in the temporal, occipital and vertebral arteries.

    PubMed

    Rehak, Z; Vasina, J; Ptacek, J; Kazda, T; Fojtik, Z; Nemec, P

    (18)F-FDG PET/CT imaging is useful in patients with fever of unknown origin and can detect giant cell arteritis in extracranial large arteries. However, it is usually assumed that temporal arteries cannot be visualized with a PET/CT scanner due to their small diameter. Three patients with clinical symptoms of temporal arteritis were examined using a standard whole body PET/CT protocol (skull base - mid thighs) followed by a head PET/CT scan using the brain protocol. High (18)F-FDG uptake in the aorta and some arterial branches were detected in all 3 patients with the whole body protocol. Using the brain protocol, head imaging led to detection of high (18)F-FDG uptake in temporal arteries as well as in their branches (3 patients), in occipital arteries (2 patients) and also in vertebral arteries (3 patients).

  2. 68Ga-DOTATOC PET/CT in Patients with Iodine- and 18F-FDG-Negative Differentiated Thyroid Carcinoma and Elevated Serum Thyroglobulin.

    PubMed

    Binse, Ina; Poeppel, Thorsten D; Ruhlmann, Marcus; Ezziddin, Samer; Görges, Rainer; Sabet, Amir; Beiderwellen, Karsten; Bockisch, Andreas; Rosenbaum-Krumme, Sandra J

    2016-10-01

    This study evaluated the impact of (68)Ga-DOTATOC PET/CT in detecting recurrence or metastases in differentiated thyroid carcinoma (DTC) patients with elevated serum thyroglobulin and both negative radioiodine imaging and negative (18)F-FDG PET/CT.

  3. 18F-FDG-PET/CT parameters as imaging biomarkers in oral cavity squamous cell carcinoma, is visual analysis of PET and contrast enhanced CT better than the numbers?

    PubMed Central

    Kendi, AT; Corey, A; Magliocca, KR; Nickleach, DC; Galt, J; Switchenko, Jeffrey M.; El-Deiry, MW; Wadsworth, JT; Hudgins, PA; Saba, NF; Schuster, DM

    2015-01-01

    Purpose This study was designed to seek associations between positron emission tomography/computed tomography (PET/CT) parameters, contrast enhanced neck computed tomography (CECT) and pathological findings, and to determine the potential prognostic value of PET/CT and CECT parameters in oral cavity squamous cell carcinoma (OCSCC). Materials and method 36 OCSCC patients underwent staging PET/CT and 30/36 of patients had CECT. PET/CT parameters were measured for the primary tumor and the hottest involved node, including maximum, mean, and peak standardized uptake values (SUV max, SUV mean, and SUV peak), metabolic tumor volume (MTV), total lesion glycolysis (TLG), standardized added metabolic activity (SAM), and normalized standardized added metabolic activity (N SAM). Qualitative assessment of PET/CT and CECT were also performed. Pathological outcomes included: perineural invasion, lymphovascular invasion, nodal extracapsular spread, grade, pathologic T and N stages. Multivariable logistic regression models were fit for each parameter and outcome adjusting for potentially confounding variables. Multivariable Cox proportional hazards models were used for progression free survival (PFS), locoregional recurrence free survival (LRFS), overall survival (OS) and distant metastasis free survival (DMFS). Results In multivariable analysis, patients with high (>=median) tumor SUV max (OR 6.3), SUV mean (OR 6.3), MTV (OR 19.0), TLG (OR 19.0), SAM (OR 11.7) and N SAM (OR 19.0) had high pathological T-stage (T3/T4) (p<0.05). Ring/heterogeneous pattern on CECT qualitative assessment was associated with worse DMFS and OS. Conclusion High PET/CT parameters were associated with pathologically advanced T stage (T3/T4). Qualitative assessment of CECT has prognostic value. PET/CT parameters did not predict clinical outcome. PMID:25816993

  4. Muscular Sarcoidosis Detected by F-18 FDG PET/CT in a Hypercalcemic Patient

    PubMed Central

    Han, Eun Ji; Jang, Yi Sun; Lee, In Suk; Lee, Jong Min; Kang, Siwon

    2013-01-01

    Sarcoidosis is a systemic granulomatous disease of unknown etiology that involves many organs, occasionally mimicking malignancy. We herein report a 50-yr-old woman of muscular sarcoidosis of chronic myopathic type, manifested by hypercalcemia and muscle wasting. Besides insignificant hilar lymphadenopathy, her sarcoidosis was confined to generalized atrophic muscles and therefore, F-18 FDG PET/CT alone among conventional imaging studies provided diagnostic clues for the non-parathyroid-related hypercalcemia. On follow-up PET/CT during low-dose steroid treatment, FDG uptake in the muscles disappeared whereas that in the hilar lymph nodes remained. PET/CT may be useful in the evaluation of unexpected disease extent and monitoring treatment response in suspected or known sarcoidosis patients. PMID:24015050

  5. 68Ga-PSMA PET/CT Uptake in Intramuscular Myxoma Imitates Prostate Cancer Metastasis.

    PubMed

    Zacho, Helle D; Nielsen, Julie B; Dettmann, Katja; Hjulskov, Sonja H; Petersen, Lars J

    2017-03-31

    Ga-PSMA PET/CT is becoming the most promising imaging modality for detecting recurrent prostate cancer. The modality has the advantage of being able to detect recurrent disease, even at very low prostate-specific antigen levels. However, several studies report Ga-PSMA uptake in tissue unrelated to prostate cancer. We present a 74-year-old man who underwent Ga-PSMA PET/CT for recurrent prostate cancer 5 years after radical prostatectomy. The Ga-PSMA PET/CT showed an intramuscular lesion with increased PSMA uptake in the left vastus medialis muscle. The lesion was surgically removed, and histopathology found it to be an intramuscular myxoma that showed immunohistochemical PSMA expression.

  6. Solitary sternal metastasis from hepatocellular carcinoma detected by F-18 FDG PET/CT.

    PubMed

    Kamaleshwaran, Koramadai Karuppusamy; Kashyap, Raghava; Bhattacharya, Anish; Mittal, Bhagwant Rai

    2013-01-01

    Fluorine-18 fluoro-deoxy-glucose positron emission tomography (F-18 FDG PET) is not sensitive modality for the diagnosis of primary hepatocellular carcinoma (HCC). However, FDG-PET imaging may be useful in the identification of extrahepatic metastases. We report an interesting image of HCC with solitary metastasis to sternum detected by F-18 FDG PET/CT.

  7. PET-CT scanner characterization for PET raw data use in biomedical research.

    PubMed

    Gianoli, Chiara; Riboldi, Marco; Kurz, Christopher; De Bernardi, Elisabetta; Bauer, Julia; Fontana, Giulia; Ciocca, Mario; Parodi, Katia; Baroni, Guido

    2014-07-01

    The purpose of this paper is to describe the experiments and methods that led to the geometrical interpretation of new-generation commercial PET-CT scanners, finalized to off-line PET-based treatment verification in ion beam therapy. Typically, the geometrical correspondence between the image domain (i.e., the dicom PET) and the sinogram domain (i.e., the PET raw data) is not explicitly described by scanner vendors. Hence, the proposed characterization can be applied to commercial PET-CT scanners used in biomedical research, for the development of technologies and methods requiring the use of PET raw data, without having access to confidential information from the vendors.

  8. Early detection of encephalitis with (18)F-FDG PET/CT.

    PubMed

    Gaeta, M C; Godani, M; Nunziata, R; Capellini, C; Ciarmiello, A

    2015-01-01

    Encephalitis is a relatively rare condition for which making an accurate diagnosis can be challenging. In fact, clinical features are not specific and structural imaging can be normal in a considerable number of cases. However, an early diagnosis is important as many forms of treatment are effective if started promptly. Even though recent guidelines do not recommend (18)F-FDG PET/CT for patients with suspected encephalitis, the case presented suggests that (18)F-FDG PET/CT may play a relevant role for the early diagnosis of this clinical condition.

  9. Prostate-Specific Membrane Antigen PET/CT: Uptake in Lymph Nodes With Active Sarcoidosis.

    PubMed

    Dias, André Henrique; Holm Vendelbo, Mikkel; Bouchelouche, Kirsten

    2017-03-01

    We describe 2 cases of Ga-PSMA PET/CT in prostate cancer patients. Both cases demonstrated symmetrical bilateral involvement of mediastinal and hilar lymph nodes besides findings in relation with prostatic disease. In both cases, endobronchial ultrasound-guided biopsy showed that the involvement of the thoracic lymph nodes was caused by nonnecrotic granulomas compatible with sarcoidosis. The cases demonstrated that increased Ga-PSMA uptake can be seen in lymph nodes with active sarcoidosis, with images mimicking those well known from FDG PET/CT. Because of these findings, granulomatous disease has to be included in the differential diagnostic evaluation of patients with Ga-PSMA-positive lymph nodes.

  10. Initial experience of Fag-PET/CT guided Imr of head-and-neck carcinoma

    SciTech Connect

    Wang Dian . E-mail: dwang@radonc.mcw.edu; Schultz, Christopher J.; Jursinic, Paul A.; Bialkowski, Mirek; Zhu, X. Ronald; Brown, W. Douglas; Rand, Scott D.; Michel, Michelle A.; Campbell, Bruce H.; Wong, Stuart; Li, X. Allen; Wilson, J. Frank

    2006-05-01

    Purpose: The purpose of this study is to evaluate the impact of {sup 18}F-fluorodeoxyglucose positron emission tomography (Fag-PET) fused with planning computed tomography (CT) on tumor localization, which guided intensity-modulated radiotherapy (Imr) of patients with head-and-neck carcinoma. Methods and Materials: From October 2002 through April 2005, we performed Fag-PET/CT guided Imr for 28 patients with head-and-neck carcinoma. Patients were immobilized with face masks that were attached with five fiducial markers. Fag-PET and planning CT scans were performed on the same flattop table in one session and were then fused. Target volumes and critical organs were contoured, and Imr plans were generated based on the fused images. Results: All 28 patients had abnormal increased uptake in Fag-PET/CT scans. PET/CT resulted in CT-based staging changes in 16 of 28 (57%) patients. PET/CT fusions were successfully performed and were found to be accurate with the use of the two commercial planning systems. Volume analysis revealed that the PET/CT-based gross target volumes (GTVs) were significantly different from those contoured from the CT scans alone in 14 of 16 patients. In addition, 16 of 28 patients who were followed for more than 6 months did not have any evidence of locoregional recurrence in the median time of 17 months. Conclusion: Fused images were found to be useful to delineate GTV required in IMRT planning. PET/CT should be considered for both initial staging and treatment planning in patients with head-and-neck carcinoma.

  11. 18F-FDG PET-CT Findings Before and After Laparoscopic Cryoablation of Small Renal Mass: An Initial Report

    PubMed Central

    Sivro, Ferida; van der Zee, Johan A.; Baars, Phillippe C.

    2015-01-01

    The aim of this study was to describe the characteristics of positron emission tomography (PET) molecular imaging combined with low-dose computed tomography (CT) in small renal mass (SRM) treated with cryoablation (CA). Currently, treatment success is defined by the absence of contrast enhancement at CT. However, the use of contrast is relatively contraindicated in patients with renal function impairment, mandating alternative follow-up strategies. Several reasons were identified as criteria for performing PET-CT before and/or after SRM-CA in 9 patients, and the results were retrospectively studied. The histology revealed renal cell carcinoma in 7 patients and oncocytoma in 2 patients. In 6 patients, a PET-CT was performed before and after CA. In one patient, the PET-CT was performed only before CA and in 2 patients only after CA. Before CA, clearly there was metabolic uptake of fluorine-18 fluorodeoxyglucose (18F-FDG) in the SRM in all patients. Following CA, the absence of 18F-FDG uptakes in the SRM could clearly be noticed. However, the tracer cannot always be distinguished from focal recurrence or reactive inflammatory tissue. In one patient, asymptomatic metastatic bone lesions were noticed when performing PET-CT at follow-up. This pilot study with 18F-FDG PET-CT for the follow-up of SRM cryosurgery showed that 18F-FDG PET-CT imaging could be used to characterize cryoablative tissue injury at different times after CA. PMID:28326272

  12. PET/CT-Based Dosimetry in 90Y-Microsphere Selective Internal Radiation Therapy: Single Cohort Comparison With Pretreatment Planning on (99m)Tc-MAA Imaging and Correlation With Treatment Efficacy.

    PubMed

    Song, Yoo Sung; Paeng, Jin Chul; Kim, Hyo-Cheol; Chung, Jin Wook; Cheon, Gi Jeong; Chung, June-Key; Lee, Dong Soo; Kang, Keon Wook

    2015-06-01

    ⁹⁰Y PET/CT can be acquired after ⁹⁰Y-microsphere selective radiation internal therapy (SIRT) to describe radioactivity distribution. We performed dosimetry using ⁹⁰Y-microsphere PET/CT data to evaluate treatment efficacy and appropriateness of activity planning from (99m)Tc-MAA scan and SPECT/CT. Twenty-three patients with liver malignancy were included in the study. (99m)Tc-MAA was injected during planning angiography and whole body (99m)Tc-MAA scan and liver SPECT/CT were acquired. After SIRT using ⁹⁰Y-resin microsphere, ⁹⁰Y-microsphere PET/CT was acquired. A partition model (PM) using 4 compartments (tumor, intarget normal liver, out-target normal liver, and lung) was adopted, and absorbed dose to each compartment was calculated based on measurements from (99m)Tc-MAA SPECT/CT and ⁹⁰Y-microsphere PET/CT, respectively, to be compared with each other. Progression-free survival (PFS) was evaluated in terms of tumor absorbed doses calculated by (99m)Tc-MAA SPECT/CT and ⁹⁰Y-microsphere PET/CT results. Lung shunt fraction was overestimated on (99m)Tc-MAA scan compared with ⁹⁰Y-microsphere PET/CT (0.060 ± 0.037 vs. 0.018 ± 0.026, P < 0.01). Tumor absorbed dose exhibited a close correlation between the results from (99m)Tc-MAA SPECT/CT and ⁹⁰Y-microsphere PET/CT (r = 0.64, P < 0.01), although the result from (99m)Tc-MAA SPECT/CT was significantly lower than that from ⁹⁰Y-microsphere PET/CT (135.4 ± 64.2 Gy vs. 185.0 ± 87.8 Gy, P < 0.01). Absorbed dose to in-target normal liver was overestimated on (99m)Tc-MAA SPECT/CT compared with PET/CT (62.6 ± 38.2 Gy vs. 45.2 ± 32.0 Gy, P = 0.02). Absorbed dose to out-target normal liver did not differ between (99m)Tc-MAA SPECT/CT and ⁹⁰Y-microsphere PET/CT (P = 0.49). Patients with tumor absorbed dose >200 Gy on ⁹⁰Y-microsphere PET/CT had longer PFS than those with tumor absorbed dose ≤200 Gy (286 ± 56 days vs. 92 ± 20

  13. Fourier-wavelet restoration in PET/CT brain studies

    NASA Astrophysics Data System (ADS)

    Knešaurek, Karin

    2012-10-01

    Our goal is to improve brain PET imaging through the application of a novel, hybrid Fourier-wavelet (WFT) restoration technique. The major limitation of PET studies is a relatively poor resolution in comparison with MRI and CT imaging and there is a need for improved PET imaging. A GE DLS PET/CT 16 slice system was used to acquire the studies. In order to create restoration filters the point source study was performed. The 6-fillable spheres and 3D Hoffman brain phantom studies were acquired and used to test and optimize the restoration approach. The patient data used in the study were acquired in a 3D PET mode, using the standard clinical protocol. Here, we have implemented Fourier-wavelet regularized restoration. In the Fourier domain, the inverse of modulation transfer function was multiplied by a Butterworth low-pass filter, order n=6 and cut-off frequency f=0.35 cycles/pixel. In addition, wavelet (Daubechies, order 2) noise suppression was applied by “hard threshold”. Hot spheres and 3D Hoffman brain studies showed that the restoration process not only improves resolution and contrast but also improves quantification in 3D PET/CT imaging. The average contrast increase was 19% and the quantification improved in the range 8-20% depending on sphere size. In the restored images, there was no significant increase in noise when compared with the original images. The clinical studies followed brain phantom findings, i.e., the restored images had better contrast and resolution properties, when compared with the original images. The results of the study demonstrate that the quality and quantification of 3D brain 18F FDG PET images can be significantly improved by Fourier-wavelet (WFT) restoration filtering.

  14. Applications of PET CT in clinical practice: Present and future

    NASA Astrophysics Data System (ADS)

    Costa, Durval Campos

    2007-02-01

    Radionuclide imaging and specially positron emission tomography (PET) has already demonstrated its benefits in three major medical subjects, i.e. neurology, cardiology and particularly clinical oncology. More recently the combination of PET and X-ray computed tomography (CT) as PET-CT led to a significant increment of the already large number of clinical applications of this imaging modality. This "anatomy-metabolic fusion" also known as Metabolic Imaging has its future assured if we can: (1) improve resolution reducing partial volume effect, (2) achieve very fast whole body imaging, (3) obtain accurate quantification of specific functions with higher contrast resolution and, if possible, (4) reduce exposure rates due to the unavoidable use of ionizing radiation.

  15. Value of PET/CT and MR Lymphography in Treatment of Prostate Cancer Patients With Lymph Node Metastases

    SciTech Connect

    Fortuin, Ansje S.; Deserno, Willem M.L.L.G.; Meijer, Hanneke J.M.; Jager, Gerrit J.; Takahashi, Satoru; Debats, Oscar A.; Reske, Sven N.; Schick, Christian; Krause, Bernd J.; Oort, Inge van; Witjes, Alfred J.; Hoogeveen, Yvonne L.; Lin, Emile N.J.Th. van; Barentsz, Jelle O.

    2012-11-01

    Purpose: To determine the clinical value of two novel molecular imaging techniques: {sup 11}C-choline positron emission tomography (PET)/computed tomography (CT) and ferumoxtran-10 enhanced magnetic resonance imaging (magnetic resonance lymphography [MRL]) for lymph node (LN) treatment in prostate cancer (PCa) patients. Therefore, we evaluated the ability of PET/CT and MRL to assess the number, size, and location of LN metastases in patients with primary or recurrent PCa. Methods and Materials: A total of 29 patients underwent MRL and PET/CT for LN evaluation. The MRL and PET/CT data were analyzed independently. The number, size, and location of the LN metastases were determined. The location was described as within or outside the standard clinical target volume for elective pelvic irradiation as defined by the Radiation Therapy Oncology Group. Subsequently, the results from MRL and PET/CT were compared. Results: Of the 738 LNs visible on MRL, 151 were positive in 23 of 29 patients. Of the 132 LNs visible on PET/CT, 34 were positive in 13 of 29 patients. MRL detected significantly more positive LNs (p < 0.001) in more patients than PET/CT (p = 0.002). The mean diameter of the detected suspicious LNs on MRL was significantly smaller than those detected by PET/CT, 4.9 mm and 8.4 mm, respectively (p < 0.0001). In 14 (61%) of 23 patients, suspicious LNs were found outside the clinical target volume with MRL and in 4 (31%) of 13 patients with PET/CT. Conclusion: In patients with PCa, both molecular imaging techniques, MRL and {sup 11}C-choline PET/CT, can detect LNs suspicious for metastasis, irrespective of the existing size and shape criteria for CT and conventional magnetic resonance imaging. On MRL and PET/CT, 61% and 31% of the suspicious LNs were located outside the conventional clinical target volume. Therefore, these techniques could help to individualize treatment selection and enable image-guided radiotherapy for patients with PCa LN metastases.

  16. Effectiveness of [(124)I]-PET/CT and [(18)F]-FDG-PET/CT for localizing recurrence in patients with differentiated thyroid carcinoma.

    PubMed

    Lee, Jandee; Nah, Kuk Young; Kim, Ra Mi; Oh, Yeon-Ju; An, Young-Sil; Yoon, Joon-Kee; An, Gwang Il; Choi, Tae Hyun; Cheon, Gi Jeong; Soh, Euy-Young; Chung, Woong Youn

    2012-09-01

    Although the prognosis of patients with differentiated thyroid carcinoma (DTC) is generally encouraging, a diagnostic dilemma is posed when an increasing level of serum thyroglobulin (Tg) is noted, without detection of a recurrent tumor using conventional imaging tools such as the iodine-131 whole-body scanning (the [(131)I] scan) or neck ultrasonography (US). The objective of the present study was to evaluate the diagnostic value of [(124)I]-PET/CT and [(18)F]-FDG-PET/CT in terms of accurate detection of both iodine- and non-iodine-avid recurrence, compared with that of conventional imaging such as the [(131)I] scan or neck ultrasonography (US). Between July 2009 and June 2010, we prospectively studied 19 DTC patients with elevated thyroglobulin levels but who do not show pathological lesions when conventional imaging modalities are used. All involved patients had undergone total thyroidectomy and radioiodine (RI) treatment, and who had been followed-up for a mean of 13 months (range, 6-21 months) after the last RI session. Combined [(18)F]-FDG-PET/CT and [(124)I]-PET/CT data were evaluated for detecting recurrent DTC lesions in study patients and compared with those of other radiological and/or cytological investigations. Nine of 19 patients (47.4%) showed pathological [(18)F]-FDG (5/19, 26.3%) or [(124)I]-PET (4/19, 21.1%) uptake, and were classed as true-positives. Among such patients, disease management was modified in six (66.7%) and disease was restaged in seven (77.8%). In particular, the use of the described imaging combination optimized planning of surgical resection to deal with locoregional recurrence in 21.1% (4/19) of patients, who were shown to be disease-free during follow-up after surgery. Our results indicate that combination of [(18)F]-FDG-PET/CT and [(124)I]-PET/CT affords a valuable diagnostic method that can be used to make therapeutic decisions in patients with DTC who are tumor-free on conventional imaging studies but who have high Tg levels.

  17. Strategies to reduce radiation dose in cardiac PET/CT

    NASA Astrophysics Data System (ADS)

    Wu, Tung Hsin; Wu, Nien-Yun; Wang, Shyh-Jen; Wu, Jay; S. P. Mok, Greta; Yang, Ching-Ching; Huang, Tzung-Chi

    2011-08-01

    Our aim was to investigate CT dose reduction strategies on a hybrid PET/CT scanner for cardiac applications.MaterialsImage quality and dose estimation of different CT scanning protocols for CT coronary angiography (CTCA), and CT-based attenuation correction for PET imaging were investigated. Fifteen patients underwent CTCA, perfusion PET imaging at rest and under stress, and FDG PET for myocardial viability. These patients were divided into three groups based on the CTCA technique performed: retrospectively gated helical (RGH), ECG tube current modulation (ETCM), and prospective gated axial (PGA) acquisitions. All emission images were corrected for photon attenuation using CT images obtained by default setting and an ultra-low dose CT (ULDCT) scan.ResultsRadiation dose in RGH technique was 22.2±4.0 mSv. It was reduced to 10.95±0.82 and 4.13±0.31 mSv using ETCM and PGA techniques, respectively. Radiation dose in CT transmission scan was reduced by 96.5% (from 4.53±0.5 to 0.16±0.01 mSv) when applying ULDCT as compared to the default CT. No significant difference in terms of image quality was found among various protocols.ConclusionThe proposed CT scanning strategies, i.e. ETCM or PGA for CTCA and ULDCT for PET attenuation correction, could reduce radiation dose up to 47% without degrading imaging quality in an integrated cardiac PET/CT coronary artery examination.

  18. Interaction of thyroid hormone with brown adipose tissue. Lessons learned from PET-CT.

    PubMed

    Steinhoff, Karen G; Hankir, M; Krause, K; Tönjes, A; Fenske, W K; Sabri, O; Hesse, S

    2015-01-01

    Brown adipose tissue (BAT) plays an important role in regulating core-body temperature in various species including man. [18F]FDG-PET/CT imaging first revealed the presence of metabolically active BAT depots and that decreased BAT function is associated with various metabolic conditions. Thyroid hormone (TH) in concert with sympathetic nervous system signalling (SNS) stimulates BAT thermogenesis and thyroid disorders result in dysfunctional BAT. Currently, research is focussing not only on BAT regulation but also on browning of white adipose tissue (WAT) to BAT beige adipose tissue (BeAT) in order to develop novel treatments for human obesity and related conditions. While [18F]FDG-PET/CT imaging is continuing to provide valuable insights into BAT and BeAT function in health and disease, there is a pressing need to develop alternative radiotracers that reliably track their activity in vivo. As a result it is expected that preclinical micro PET/CT investigations of BAT and BeAT will gain in prominence. The aim of this short review is to i) describe fundamentals in BAT biology, ii) highlight some of the clinical and preclinical studies performed on humans and rodents with a focus on TH, BAT and PET/CT, and iii) bridge these data with our own studies within the DFG thyroid transact priority program.

  19. 68Ga-PRGD2 PET/CT in the Evaluation of Glioma: A Prospective Study

    PubMed Central

    2015-01-01

    Integrin αvβ3 is overexpressed in both neovasculature and glioma cells. We aimed to evaluate 68gallium-BNOTA-PRGD2 (68Ga-PRGD2) as a new reagent for noninvasive integrin αvβ3 imaging in glioma patients. With informed consent, 12 patients with suspicious brain glioma, as diagnosed by enhanced magnetic resonance imaging (MRI) scanning, were enrolled to undergo 68Ga-PRGD2 PET/CT and 18F-FDG PET/CT scans before surgery. The preoperative images were compared and correlated with the pathologically determined WHO grade. Next, the expression of integrin αvβ3, CD34, and Ki-67 were determined by immunohistochemical staining of the resected brain tumor tissue. Our findings demonstrated that 68Ga-PRGD2 specifically accumulated in the brain tumors that were rich of integrin αvβ3 and other neovasculature markers, but not in the brain parenchyma other than the choroid plexus. Therefore, 68Ga-PRGD2 PET/CT was able to evaluate the glioma demarcation more specifically than 18F-FDG PET/CT. The maximum standardized uptake values (SUVmax) of 68Ga-PRGD2, rather than those of 18F-FDG, were significantly correlated with the glioma grading. The maximum tumor-to-brain ratios (TBRmax) of both tracers were significantly correlated with glioma grading, whereas 68Ga-PRGD2 seemed to be more superior to 18F-FDG in differentiating high-grade glioma (HGG) from low-grade glioma (LGG). Moreover, 68Ga-PRGD2 PET/CT showed different accumulation patterns for HGG of WHO grades III and IV. This is the first noninvasive integrin imaging study, to the best of our knowledge, conducted in preoperative patients with different grades of glioma, and it preliminarily indicated the effectiveness of this novel method for evaluating glioma grading and demarcation. PMID:25093246

  20. Role of 18F-FDG-PET/CT in the management of marginal zone B cell lymphoma.

    PubMed

    Carrillo-Cruz, Estrella; Marín-Oyaga, Victor A; de la Cruz Vicente, Fátima; Borrego-Dorado, Isabel; Ruiz Mercado, Marta; Acevedo Báñez, Irene; Solé Rodríguez, Maria; Fernández López, Rosa; Pérez Vega, Herminia; Calderón-Cabrera, Cristina; Espigado Tocino, Ildefonso; Pérez-Simón, Jose A; Vázquez-Albertino, Ricardo

    2015-12-01

    The use of PET in patients with marginal zone B cell lymphoma (MZL) is controversial because of variability of fluorodeoxyglucose (FDG) avidity. We analyzed 40 PET/CT in 25 consecutive patients to compare its performance with CT at staging and as a first-line response assessment. Sensitivity of PET/CT and CT was 96 and 76%. Mean standard uptake value was 6.1, 6.9 and 3.4 (p = 0.3) in nodal, extranodal and splenic subtypes, respectively. Of 17 patients (extranodal: n = 9; nodal: n = 6; splenic subtype: n = 2) with both imaging tests available at diagnosis, 8 (47%) had more involved areas with PET/CT than with CT, 75% of which were extranodal lesions. PET/CT resulted in upstaging of five patients although treatment of only two of them was changed. Responses of 15 patients with post-treatment PET/CT were the following: 9 negative and 6 positive of which 3 were isolated residual lesions. Progression was documented in two of these three patients. Response was also assessed by CT in 11 patients. Discrepancies were found in three: Two were in complete remission by CT while PET/CT detected localized residual disease; another patient was in partial remission by CT, whereas PET/CT showed only one positive lesion. Two of these three patients relapsed. Patients with negative post-treatment PET/CT did not relapse. With a median follow-up of 50 months (10-152 months), 3-year overall survival was 100 and 80% for patients with negative and positive post-treatment PET/CT (p = 0.2). Three-year disease-free survival was 86%; the negative predictive value (NPV) was 100%, and the positive predictive value (PPV) was 83.3%. Although a larger number of patients will be required to further confirm these data, we can conclude that PET/CT is a useful imaging tool for both staging and response assessment in patients with nodal and extranodal MZL as a result of its high sensitivity, NPV and PPV.

  1. Thoracic cavity definition for 3D PET/CT analysis and visualization.

    PubMed

    Cheirsilp, Ronnarit; Bascom, Rebecca; Allen, Thomas W; Higgins, William E

    2015-07-01

    X-ray computed tomography (CT) and positron emission tomography (PET) serve as the standard imaging modalities for lung-cancer management. CT gives anatomical details on diagnostic regions of interest (ROIs), while PET gives highly specific functional information. During the lung-cancer management process, a patient receives a co-registered whole-body PET/CT scan pair and a dedicated high-resolution chest CT scan. With these data, multimodal PET/CT ROI information can be gleaned to facilitate disease management. Effective image segmentation of the thoracic cavity, however, is needed to focus attention on the central chest. We present an automatic method for thoracic cavity segmentation from 3D CT scans. We then demonstrate how the method facilitates 3D ROI localization and visualization in patient multimodal imaging studies. Our segmentation method draws upon digital topological and morphological operations, active-contour analysis, and key organ landmarks. Using a large patient database, the method showed high agreement to ground-truth regions, with a mean coverage=99.2% and leakage=0.52%. Furthermore, it enabled extremely fast computation. For PET/CT lesion analysis, the segmentation method reduced ROI search space by 97.7% for a whole-body scan, or nearly 3 times greater than that achieved by a lung mask. Despite this reduction, we achieved 100% true-positive ROI detection, while also reducing the false-positive (FP) detection rate by >5 times over that achieved with a lung mask. Finally, the method greatly improved PET/CT visualization by eliminating false PET-avid obscurations arising from the heart, bones, and liver. In particular, PET MIP views and fused PET/CT renderings depicted unprecedented clarity of the lesions and neighboring anatomical structures truly relevant to lung-cancer assessment.

  2. Focal Colonic FDG Activity with PET/CT: Guidelines for Recommendation of Colonoscopy

    PubMed Central

    Liu, Tianye; Behr, Spencer; Khan, Sana; Osterhoff, Robert; Aparici, Carina Mari

    2015-01-01

    Focal 18F-fluorodeoxyglucose (FDG) colonic activity can be incidentally seen in positron emission tomography/computed tomography (PET/CT) scans. Its clinical significance is still unclear. The purpose of this study was to assess the significance of focal FDG activity in PET/CT scans by correlating the imaging findings to colonoscopy results, and come up with some guidelines for recommendation of follow-up colonoscopy. A total of 133 patients who underwent both 18F-FDG PET/CT for different oncological indications and colonoscopy within 3 months were retrospectively studied. Imaging, colonoscopy and pathology results were analyzed. Of the 133 FDG-PET/CT scans, 109/133 (82%) did not show focal colonic FDG activity, and 24/133 (18%) did. Of the 109/133 PET/CTs without focal colonic FDG activity, 109/109 (100%) did not have evidence of colon cancer after colonoscopy and histology. Of the 24/133 PET/CTs with focal colonic FDG activity, 10/24 (42%) had pathologic confirmation of colon cancer and 14/24 (58%) did not have evidence of colon cancer after colonoscopy and histological analysis. Sensitivity was 10/10 (100%), specificity 109/123 (89%), positive predictive value (PPV) 10/24 (42%) and negative predictive value (NPV) 109/109 (100%). Incidental focal 18FDG activity in PET/CT imaging shows a high sensitivity, specificity and NPV for malignancy, with a not so high PPV of 42%. Although some people would argue that a 42% chance of malignancy justifies colonoscopy, this maybe is not possible in all cases. However, the high sensitivity of the test does not allow these studies to be overlooked. We provide our recommendations as per when to send patients with focal FDG colonic activity to have further characterization with colonoscopy. PMID:25709541

  3. Thoracic Cavity Definition for 3D PET/CT Analysis and Visualization

    PubMed Central

    Cheirsilp, Ronnarit; Bascom, Rebecca; Allen, Thomas W.; Higgins, William E.

    2015-01-01

    X-ray computed tomography (CT) and positron emission tomography (PET) serve as the standard imaging modalities for lung-cancer management. CT gives anatomical detail on diagnostic regions of interest (ROIs), while PET gives highly specific functional information. During the lung-cancer management process, a patient receives a co-registered whole-body PET/CT scan pair and a dedicated high-resolution chest CT scan. With these data, multimodal PET/CT ROI information can be gleaned to facilitate disease management. Effective image segmentation of the thoracic cavity, however, is needed to focus attention on the central chest. We present an automatic method for thoracic cavity segmentation from 3D CT scans. We then demonstrate how the method facilitates 3D ROI localization and visualization in patient multimodal imaging studies. Our segmentation method draws upon digital topological and morphological operations, active-contour analysis, and key organ landmarks. Using a large patient database, the method showed high agreement to ground-truth regions, with a mean coverage = 99.2% and leakage = 0.52%. Furthermore, it enabled extremely fast computation. For PET/CT lesion analysis, the segmentation method reduced ROI search space by 97.7% for a whole-body scan, or nearly 3 times greater than that achieved by a lung mask. Despite this reduction, we achieved 100% true-positive ROI detection, while also reducing the false-positive (FP) detection rate by >5 times over that achieved with a lung mask. Finally, the method greatly improved PET/CT visualization by eliminating false PET-avid obscurations arising from the heart, bones, and liver. In particular, PET MIP views and fused PET/CT renderings depicted unprecedented clarity of the lesions and neighboring anatomical structures truly relevant to lung-cancer assessment. PMID:25957746

  4. Ferret thoracic anatomy by 2-deoxy-2-(18F)fluoro-D-glucose (18F-FDG) positron emission tomography/computed tomography (18F-FDG PET/CT) imaging.

    PubMed

    Wu, Albert; Zheng, Huaiyu; Kraenzle, Jennifer; Biller, Ashley; Vanover, Carol D; Proctor, Mary; Sherwood, Leslie; Steffen, Marlene; Ng, Chin; Mollura, Daniel J; Jonsson, Colleen B

    2012-01-01

    The domestic ferret (Mustela putorius furo) has been a long-standing animal model used in the evaluation and treatment of human diseases. Molecular imaging techniques such as 2-deoxy-2-((18)F)fluoro-D-glucose ((18)F-FDG) positron emission tomography (PET) would be an invaluable method of tracking disease in vivo, but this technique has not been reported in the literature. Thus, the aim of this study was to establish baseline imaging characteristics of PET/computed tomography (CT) with (18)F-FDG in the ferret model. Twelve healthy female ferrets were anesthetized and underwent combined PET/CT scanning. After the images were fused, volumes of interest (VOIs) were generated in the liver, heart, thymus, and bilateral lung fields. For each VOI, standardized uptake values (SUVs) were calculated. Additional comparisons were made between radiotracer uptake periods (60, 90, and >90 minutes), intravenous and intraperitoneal injections of (18)F-FDG, and respiratory gated and ungated acquisitions. Pulmonary structures and the surrounding thoracic and upper abdominal anatomy were readily identified on the CT scans of all ferrets and were successfully fused with PET. VOIs were created in various tissues with the following SUV calculations: heart (maximum standardized uptake value [SUV(Max)] 8.60, mean standardized uptake value [SUV(Mean)] 5.42), thymus (SUV(Max) 3.86, SUV(Mean) 2.59), liver (SUV(Max) 1.37, SUV(Mean) 0.99), right lung (SUV(Max) 0.92, SUV(Mean) 0.56), and left lung (SUV(Max) 0.88, SUV(Mean) 0.51). Sixty- to 90-minute uptake periods were sufficient to separate tissues based on background SUV activity. No gross differences in image quality were seen between intraperitoneal and intravenous injections of (18)F-FDG. Respiratory gating also did not have a significant impact on image quality of lung parenchyma. The authors concluded that (18)F-FDG PET and CT imaging can be performed successfully in normal healthy ferrets with the parameters identified in this study. They

  5. Ferret Thoracic Anatomy by 2-Deoxy-2-(18F)Fluoro-D-Glucose (18F-FDG) Positron Emission Tomography/Computed Tomography (18F-FDG PET/CT) Imaging

    PubMed Central

    Wu, Albert; Zheng, Huaiyu; Kraenzle, Jennifer; Biller, Ashley; Vanover, Carol D.; Proctor, Mary; Sherwood, Leslie; Steffen, Marlene; Ng, Chin; Mollura, Daniel J.; Jonsson, Colleen B.

    2013-01-01

    The domestic ferret (Mustela putorius furo) has been a long-standing animal model used in the evaluation and treatment of human diseases. Molecular imaging techniques such as 2-deoxy-2-(18F)fluoro-D-glucose (18F-FDG) positron emission tomography (PET) would be an invaluable method of tracking disease in vivo, but this technique has not been reported in the literature. Thus, the aim of this study was to establish baseline imaging characteristics of PET/computed tomography (CT) with 18F-FDG in the ferret model. Twelve healthy female ferrets were anesthetized and underwent combined PET/CT scanning. After the images were fused, volumes of interest (VOIs) were generated in the liver, heart, thymus, and bilateral lung fields. For each VOI, standardized uptake values (SUVs) were calculated. Additional comparisons were made between radiotracer uptake periods (60, 90, and >90 minutes), intravenous and intraperitoneal injections of 18F-FDG, and respiratory gated and ungated acquisitions. Pulmonary structures and the surrounding thoracic and upper abdominal anatomy were readily identified on the CT scans of all ferrets and were successfully fused with PET. VOIs were created in various tissues with the following SUV calculations: heart (maximum standardized uptake value [SUVMax] 8.60, mean standardized uptake value [SUVMean] 5.42), thymus (SUVMax 3.86, SUVMean 2.59), liver (SUVMax 1.37, SUVMean 0.99), right lung (SUVMax 0.92, SUVMean 0.56), and left lung (SUVMax 0.88, SUVMean 0.51). Sixty- to 90-minute uptake periods were sufficient to separate tissues based on background SUV activity. No gross differences in image quality were seen between intraperitoneal and intravenous injections of 18F-FDG. Respiratory gating also did not have a significant impact on image quality of lung parenchyma. The authors concluded that 18F-FDG PET and CT imaging can be performed successfully in normal healthy ferrets with the parameters identified in this study. They obtained similar imaging

  6. Role of (68)Ga-DOTATATE PET/CT in patients with multiple endocrine neoplasia type 1 (MEN1).

    PubMed

    Lastoria, Secondo; Marciello, Francesca; Faggiano, Antongiulio; Aloj, Luigi; Caracò, Corradina; Aurilio, Michela; D'Ambrosio, Laura; Di Gennaro, Francesca; Ramundo, Valeria; Camera, Luigi; De Luca, Leonardo; Fonti, Rosa; Napolitano, Vincenzo; Colao, Annamaria

    2016-06-01

    Multiple endocrine neoplasia type 1 (MEN1) is a hereditary syndrome predisposing to many endocrine and neuroendocrine tumors (NET). Conventional imaging (CI) cannot provide satisfactory results for all the different types of MEN1-related tumors. Objective of this prospective observational study was to evaluate the role of (68)Ga-DOTATATE PET/CT in MEN1 compared to CI. Diagnostic performance of (68)Ga-DOTATATE PET/CT for the detection of NET was evaluated as well as the prognostic role of SUVmax. Eighteen patients with genetically confirmed MEN1 were evaluated by (68)Ga-DOTATATE PET/CT, endoscopic ultrasounds, multidetector-row computed tomography, magnetic resonance imaging, and hormone/markers serum measurements. Four MEN1-related tumor sites (pancreas, pituitary, parathyroids, adrenals) were considered. Sensitivity and specificity of (68)Ga-DOTATATE PET/CT for the detection of NET were calculated. There was (68)Ga-DOTATATE PET/CT uptake in 11/11 patients with pancreatic lesions, in 9/12 with pituitary adenoma, in 5/15 with parathyroid enlargements, and in 5/7 with adrenal lesions. (68)Ga-DOTATATE PET/CT showed sensitivity and specificity of 100 and 100 % in pancreas, 75 and 83 % in pituitary, 28 and 100 % in parathyroids, and 62.5 and 100 % in adrenals, respectively. Compared with CI, no significant difference in sensitivity for pancreas, pituitary, and adrenals was found, while CI had a better sensitivity for parathyroids (p = 0.002). On the ROC analysis, progression of pancreatic lesions was significantly associated to SUVmax <12.3 (p < 0.05). (68)Ga-DOTATATE PET/CT is greatly helpful in the work-up of MEN1 providing a panoramic view of MEN1-related lesions. There is also a prognostic role of (68)Ga-PET in patients with MEN1-pancreatic lesions.

  7. Clinical significance of incidental FDG uptake in the prostate gland detected by PET/CT

    PubMed Central

    Sahin, Ertan; Elboga, Umut; Kalender, Ebuzer; Basıbuyuk, Mustafa; Demir, Hasan Deniz; Celen, Yusuf Zeki

    2015-01-01

    The value of FDG-positron emission tomography/computed tomography (PET/CT) for detecting prostate cancer is unknown. We aimed to investigate the clinical value of incidental prostate FDG uptake on PET/CT scans. We reviewed 6128 male patients who underwent FDG-PET/CT scans and selected cases that reported hypermetabolic lesion in the prostate. The patients who have prior history of prostate carcinoma or prostate surgery were excluded from the study. We have analyzed the correlation between PET/CT findings and serum prostate-specific antigen (PSA) levels, imaging (USG), urological examinations and biopsy. Incidental 18F-FDG uptake of the prostate gland was observed in 79 patients (1.3%). While sixteen of them were excluded due to inadequate clinical data, the remaining 63 patients were included for further analysis. The patients were divided into two groups; 8 patients (12.7%) in the malignant group and 55 patients (87.3%) in the benign group. The SUVmax values were not significantly different between the two groups. In 6 (75%) patients with prostate cancer, FDG uptake was observed focally in the peripheral zone of the prostate glands. There was no significant correlation between the SUVmax and the PSA levels. Incidental 18F-FDG uptake in the prostate gland is a rare condition, but a substantial portion of it is associated with the cancer. Benign and malignant lesions of the prostate gland in FDG-PET/CT imaging could not be reliably distinguished. The peripheral focally FDG uptake of prostate glands should be further examined with the clinical and labaratory evaluations. PMID:26379847

  8. Optimization of image reconstruction for yttrium-90 SIRT on a LYSO PET/CT system using a Bayesian penalized likelihood reconstruction algorithm.

    PubMed

    Rowley, Lisa M; Bradley, Kevin M; Boardman, Philip; Hallam, Aida; McGowan, Daniel R

    2016-09-29

    Imaging on a gamma camera with Yttrium-90 ((90)Y) following selective internal radiotherapy (SIRT) may allow for verification of treatment delivery but suffers relatively poor spatial resolution and imprecise dosimetry calculation. (90)Y Positron Emission Tomography (PET) / Computed Tomography (CT) imaging is possible on 3D, time-of-flight machines however images are usually poor due to low count statistics and noise. A new PET reconstruction software using a Bayesian penalized likelihood (BPL) reconstruction algorithm (termed Q.Clear) released by GE was investigated using phantom and patient scans to optimize the reconstruction for post-SIRT imaging and clarify if this leads to an improvement in clinical image quality using (90)Y.

  9. Evaluation of Cross-Calibrated 68Ge/68Ga Phantoms for Assessing PET/CT Measurement Bias in Oncology Imaging for Single- and Multicenter Trials

    PubMed Central

    Byrd, Darrin W.; Doot, Robert K.; Allberg, Keith C.; MacDonald, Lawrence R.; McDougald, Wendy A.; Elston, Brian F.; Linden, Hannah M.; Kinahan, Paul E.

    2016-01-01

    Quantitative PET imaging is an important tool for clinical trials evaluating the response of cancers to investigational therapies. The standardized uptake value, used as a quantitative imaging biomarker, is dependent on multiple parameters that may contribute bias and variability. The use of long-lived, sealed PET calibration phantoms offers the advantages of known radioactivity activity concentration and simpler use than aqueous phantoms. We evaluated scanner and dose calibrator sources from two batches of commercially available kits, together at a single site and distributed across a local multicenter PET imaging network. We found that radioactivity concentration was uniform within the phantoms. Within the regions of interest drawn in the phantom images, coefficients of variation of voxel values were less than 2%. Across phantoms, coefficients of variation for mean signal were close to 1%. Biases of the standardized uptake value estimated with the kits varied by site and were seen to change in time by approximately ±5%. We conclude that these biases cannot be assumed constant over time. The kits provide a robust method to monitor PET scanner and dose calibrator biases, and resulting biases in standardized uptake values. PMID:28066807

  10. Combined PET/CT with iodine-124 in diagnosis of spread metastatic thyroid carcinoma: a case report.

    PubMed

    Freudenberg, L S; Antoch, G; Görges, R; Knust, J; Pink, R; Jentzen, W; Debatin, J F; Brandau, W; Bockisch, A; Stattaus, J

    2003-12-01

    Iodine-124 positron emission tomography (PET) is a useful 3D imaging technique for diagnosis and management of thyroid diseases. The difficulty in interpretation of the PET scans with highly selective tracers, such as iodine-124, is the lack of identifiable anatomical structures, so an accurate anatomical localization of foci presenting abnormal uptake is problematic. Consequently, a combined PET/CT scanner can resolve these difficulties by co-registering PET and CT data in a single session allowing a correlation of functional and morphologic imaging. A case is presented where iodine-124 produced by a clinical cyclotron and FDG were used to acquire images with a combined PET/CT scanner for clinical staging. On the basis of the PET/CT exams the treatment of the patient was modified.

  11. TU-F-12A-05: Sensitivity of Textural Features to 3D Vs. 4D FDG-PET/CT Imaging in NSCLC Patients

    SciTech Connect

    Yang, F; Nyflot, M; Bowen, S; Kinahan, P; Sandison, G

    2014-06-15

    Purpose: Neighborhood Gray-level difference matrices (NGLDM) based texture parameters extracted from conventional (3D) 18F-FDG PET scans in patients with NSCLC have been previously shown to associate with response to chemoradiation and poorer patient outcome. However, the change in these parameters when utilizing respiratory-correlated (4D) FDG-PET scans has not yet been characterized for NSCLC. The Objectives: of this study was to assess the extent to which NGLDM-based texture parameters on 4D PET images vary with reference to values derived from 3D scans in NSCLC. Methods: Eight patients with newly diagnosed NSCLC treated with concomitant chemoradiotherapy were included in this study. 4D PET scans were reconstructed with OSEM-IR in 5 respiratory phase-binned images and corresponding CT data of each phase were employed for attenuation correction. NGLDM-based texture features, consisting of coarseness, contrast, busyness, complexity and strength, were evaluated for gross tumor volumes defined on 3D/4D PET scans by radiation oncologists. Variation of the obtained texture parameters over the respiratory cycle were examined with respect to values extracted from 3D scans. Results: Differences between texture parameters derived from 4D scans at different respiratory phases and those extracted from 3D scans ranged from −30% to 13% for coarseness, −12% to 40% for contrast, −5% to 50% for busyness, −7% to 38% for complexity, and −43% to 20% for strength. Furthermore, no evident correlations were observed between respiratory phase and 4D scan texture parameters. Conclusion: Results of the current study showed that NGLDM-based texture parameters varied considerably based on choice of 3D PET and 4D PET reconstruction of NSCLC patient images, indicating that standardized image acquisition and analysis protocols need to be established for clinical studies, especially multicenter clinical trials, intending to validate prognostic values of texture features for NSCLC.

  12. Evaluation of Prostate Cancer Bone Metastases with 18F-NaF and 18F-Fluorocholine PET/CT.

    PubMed

    Beheshti, Mohsen; Rezaee, Alireza; Geinitz, Hans; Loidl, Wolfgang; Pirich, Christian; Langsteger, Werner

    2016-10-01

    (18)F-fluorocholine is a specific promising agent for imaging tumor cell proliferation, particularly in prostate cancer, using PET/CT. It is a beneficial tool in the early detection of marrow-based metastases because it excludes distant metastases and evaluates the response to hormone therapy. In addition, (18)F-fluorocholine has the potential to differentiate between degenerative and malignant osseous abnormalities because degenerative changes are not choline-avid; however, the agent may accumulate in recent traumatic bony lesions. On the other hand, (18)F-NaF PET/CT can indicate increased bone turnover and is generally used in the assessment of primary and secondary osseous malignancies, the evaluation of response to treatment, and the clarification of abnormalities on other imaging modalities or clinical data. (18)F-NaF PET/CT is a highly sensitive method in the evaluation of bone metastases from prostate cancer, but it has problematic specificity, mainly because of tracer accumulation in degenerative and inflammatory bone diseases. In summary, (18)F-NaF PET/CT is a highly sensitive method, but (18)F-fluorocholine PET/CT can detect early bone marrow metastases and provide greater specificity in the detection of bone metastases in patients with prostate cancer. However, the difference seems not to be significant.

  13. Dose Optimization in TOF-PET/MR Compared to TOF-PET/CT

    PubMed Central

    Queiroz, Marcelo A.; Delso, Gaspar; Wollenweber, Scott; Deller, Timothy; Zeimpekis, Konstantinos; Huellner, Martin; de Galiza Barbosa, Felipe; von Schulthess, Gustav; Veit-Haibach, Patrick

    2015-01-01

    Purpose To evaluate the possible activity reduction in FDG-imaging in a Time-of-Flight (TOF) PET/MR, based on cross-evaluation of patient-based NECR (noise equivalent count rate) measurements in PET/CT, cross referencing with phantom-based NECR curves as well as initial evaluation of TOF-PET/MR with reduced activity. Materials and Methods A total of 75 consecutive patients were evaluated in this study. PET/CT imaging was performed on a PET/CT (time-of-flight (TOF) Discovery D 690 PET/CT). Initial PET/MR imaging was performed on a newly available simultaneous TOF-PET/MR (Signa PET/MR). An optimal NECR for diagnostic purposes was defined in clinical patients (NECRP) in PET/CT. Subsequent optimal activity concentration at the acquisition time ([A]0) and target NECR (NECRT) were obtained. These data were used to predict the theoretical FDG activity requirement of the new TOF-PET/MR system. Twenty-five initial patients were acquired with (retrospectively reconstructed) different imaging times equivalent for different activities on the simultaneous PET/MR for the evaluation of clinically realistic FDG-activities. Results The obtained values for NECRP, [A]0 and NECRT were 114.6 (± 14.2) kcps (Kilocounts per second), 4.0 (± 0.7) kBq/mL and 45 kcps, respectively. Evaluating the NECRT together with the phantom curve of the TOF-PET/MR device, the theoretical optimal activity concentration was found to be approximately 1.3 kBq/mL, which represents 35% of the activity concentration required by the TOF-PET/CT. Initial evaluation on patients in the simultaneous TOF-PET/MR shows clinically realistic activities of 1.8 kBq/mL, which represent 44% of the required activity. Conclusion The new TOF-PET/MR device requires significantly less activity to generate PET-images with good-to-excellent image quality, due to improvements in detector geometry and detector technologies. The theoretically achievable dose reduction accounts for up to 65% but cannot be fully translated into clinical

  14. Nanoparticles in Higher-Order Multimodal Imaging

    NASA Astrophysics Data System (ADS)

    Rieffel, James Ki

    Imaging procedures are a cornerstone in our current medical infrastructure. In everything from screening, diagnostics, and treatment, medical imaging is perhaps our greatest tool in evaluating individual health. Recently, there has been tremendous increase in the development of multimodal systems that combine the strengths of complimentary imaging technologies to overcome their independent weaknesses. Clinically, this has manifested in the virtually universal manufacture of combined PET-CT scanners. With this push toward more integrated imaging, new contrast agents with multimodal functionality are needed. Nanoparticle-based systems are ideal candidates based on their unique size, properties, and diversity. In chapter 1, an extensive background on recent multimodal imaging agents capable of enhancing signal or contrast in three or more modalities is presented. Chapter 2 discusses the development and characterization of a nanoparticulate probe with hexamodal imaging functionality. It is my hope that the information contained in this thesis will demonstrate the many benefits of nanoparticles in multimodal imaging, and provide insight into the potential of fully integrated imaging.

  15. Distribution Atlas of Proliferating Bone Marrow in Non-Small Cell Lung Cancer Patients Measured by FLT-PET/CT Imaging, With Potential Applicability in Radiation Therapy Planning

    SciTech Connect

    Campbell, Belinda A.; Callahan, Jason; Bressel, Mathias; Simoens, Nathalie; Everitt, Sarah; Hofman, Michael S.; Hicks, Rodney J.; Burbury, Kate; MacManus, Michael

    2015-08-01

    Purpose: Proliferating bone marrow is exquisitely sensitive to ionizing radiation. Knowledge of its distribution could improve radiation therapy planning to minimize unnecessary marrow exposure and avoid consequential prolonged myelosuppression. [18F]-Fluoro-3-deoxy-3-L-fluorothymidine (FLT)–positron emission tomography (PET) is a novel imaging modality that provides detailed quantitative images of proliferating tissues, including bone marrow. We used FLT-PET imaging in cancer patients to produce an atlas of marrow distribution with potential clinical utility. Methods and Materials: The FLT-PET and fused CT scans of eligible patients with non-small cell lung cancer (no distant metastases, no prior cytotoxic exposure, no hematologic disorders) were reviewed. The proportions of skeletal FLT activity in 10 predefined bony regions were determined and compared according to age, sex, and recent smoking status. Results: Fifty-one patients were studied: 67% male; median age 68 (range, 31-87) years; 8% never smokers; 70% no smoking in the preceding 3 months. Significant differences in marrow distribution occurred between sex and age groups. No effect was detected from smoking in the preceding 3 months. Using the mean percentages of FLT uptake per body region, we created an atlas of the distribution of functional bone marrow in 4 subgroups defined by sex and age. Conclusions: This atlas has potential utility for estimating the distribution of active marrow in adult cancer patients to guide radiation therapy planning. However, because of interindividual variation it should be used with caution when radiation therapy risks ablating large proportions of active marrow; in such cases, individual FLT-PET scans may be required.

  16. The role of early 18F-FDG PET/CT in therapeutic management and ongoing risk stratification of high/intermediate-risk thyroid carcinoma.

    PubMed

    Triviño Ibáñez, E M; Muros, M A; Torres Vela, E; Llamas Elvira, J M

    2016-03-01

    Little is known about the role in ongoing risk stratification of fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) performed early after radioactive iodine (RAI) ablation in differentiated thyroid carcinoma (DTC). The aim of the study is to investigate whether 18F-FDG PET/CT performed early after RAI ablation is useful to detect disease and to influence therapy and ongoing risk stratification. Patients with high/intermediate risk of recurrent DTC were included. 18F-FDG PET/CT scan was performed within 6 months after RAI ablation. We confirmed results with other imaging techniques, pathology reports, or follow-up. We classified the patient response as excellent, acceptable, or incomplete. Modified Hicks criteria were used to evaluate clinical impact. We included 81 patients with high/intermediate risk of recurrent DTC. Forty-one (50.6%) had positive uptake in 18F-FDG PET/CT, with negative (131)I whole-body scan ((131)I WBS). Sensitivity, specificity, and diagnostic accuracy of 18F-FDG PET/CT were 92.5, 90.2, and 91.4%, respectively. 18F-FDG PET/CT results had an impact on therapy in 38.3% of patients. One year after initial therapy, 45.7% showed excellent response, 8.6% acceptable response, and 45.7% incomplete response. A statistically significant relationship was found between negative 18F-FDG PET/CT and excellent response (80 vs. 12.2%, p < 0.001; OR 52.8). 18F-FDG PET/CT scan performed early in surveillance of patients with high/intermediate-risk thyroid carcinoma provides important additional information not available with conventional follow-up methods and had a high impact on therapy. A negative 18F-FDG PET/CT predicts an excellent response to therapy in the new ongoing risk stratification.

  17. Preliminary results on the role of PET/CT in initial staging, restaging, and management of lung cancer

    NASA Astrophysics Data System (ADS)

    Malamitsi, J.; Valotassiou, B.; Iliadis, K.; Kosmidis, P.; Laspas, F.; Vasilaki, M.; Pipini, E.; Petounis, A.; Gogou, L.; Pagou, M.; Dalianis, K.; Efthimiadou, R.; Andreou, J.

    2006-12-01

    AimTo determine true-positive and true-negative rates of PET/CT studies in the staging of lung cancer as compared with conventional imaging (CT and bone scan and occasionally MRI) and the impact of PET/CT on the treatment strategy in patients with lung cancer. Materials and methodTwenty patients (21 studies) with known or suspected lung cancer (14 patients with non-small-cell lung cancer (NSCLC), three patients with small-cell lung cancer (SCLC), three patients with solitary pulmonary nodule underwent initial staging (seven studies) or restaging (14 studies) with combined FDG PET and CT scans on a PET/CT tomograph. PET/CT images were evaluated separately by two nuclear medicine physicians and two radiologists specialized on PET, CT, and MRI. Histology results and a more than 6 months follow-up served as the reference standards. ResultsAccurate diagnosis was achieved on 16 studies. Site-by-site analysis gave the following results: 16 true-positive sites (seven on histology, nine on >6 months follow-up), six true-negative sites (two on histology, four on >6 months follow-up). On PET/CT, six patients were correctly down-staged, three patients were correctly upstaged and seven patients were diagnosed correctly as being on the same stage (2/7 with increase of extent of disease, 5/7 with the same extent of disease). One patient was falsely upstaged and three patients were falsely down-staged. On the basis of PET/CT results, change of management was induced in six patients, while in 14 patients there was no change induced. In five cases PET/CT was partially accurate: on site-by-site analysis, four sites proved true positive (on histology), one site false positive (on histology), and four sites false negative (one on histology, three on >6 months follow-up). ConclusionIn our early experience, PET/CT contributed significantly to correct staging and management of patients with lung cancer.

  18. Pilot Preclinical and Clinical Evaluation of (4S)-4-(3-[18F]Fluoropropyl)-L-Glutamate (18F-FSPG) for PET/CT Imaging of Intracranial Malignancies

    PubMed Central

    Mittra, Erik S.; Koglin, Norman; Mosci, Camila; Kumar, Meena; Hoehne, Aileen; Keu, Khun Visith; Iagaru, Andrei H.; Mueller, Andre; Berndt, Mathias; Bullich, Santiago; Friebe, Matthias; Schmitt-Willich, Heribert; Gekeler, Volker; Fels, Lüder M.; Bacher-Stier, Claudia; Moon, Dae Hyuk; Chin, Frederick T.; Stephens, Andrew W.; Dinkelborg, Ludger M.; Gambhir, Sanjiv S.

    2016-01-01

    Purpose (S)-4-(3-[18F]Fluoropropyl)-L-glutamic acid (18F-FSPG) is a novel radiopharmaceutical for Positron Emission Tomography (PET) imaging. It is a glutamate analogue that can be used to measure xC- transporter activity. This study was performed to assess the feasibility of 18F-FSPG for imaging orthotopic brain tumors in small animals and the translation of this approach in human subjects with intracranial malignancies. Experimental Design For the small animal study, GS9L glioblastoma cells were implanted into brains of Fischer rats and studied with 18F-FSPG, the 18F-labeled glucose derivative 18F-FDG and with the 18F-labeled amino acid derivative 18F-FET. For the human study, five subjects with either primary or metastatic brain cancer were recruited (mean age 50.4 years). After injection of 300 MBq of 18F-FSPG, 3 whole-body PET/Computed Tomography (CT) scans were obtained and safety parameters were measured. The three subjects with brain metastases also had an 18F-FDG PET/CT scan. Quantitative and qualitative comparison of the scans was performed to assess kinetics, biodistribution, and relative efficacy of the tracers. Results In the small animals, the orthotopic brain tumors were visualized well with 18F-FSPG. The high tumor uptake of 18F-FSPG in the GS9L model and the absence of background signal led to good tumor visualization with high contrast (tumor/brain ratio: 32.7). 18F-FDG and 18F-FET showed T/B ratios of 1.7 and 2.8, respectively. In the human pilot study, 18F-FSPG was well tolerated and there was similar distribution in all patients. All malignant lesions were positive with 18F-FSPG except for one low-grade primary brain tumor. In the 18F-FSPG-PET-positive tumors a similar T/B ratio was observed as in the animal model. Conclusions 18F-FSPG is a novel PET radiopharmaceutical that demonstrates good uptake in both small animal and human studies of intracranial malignancies. Future studies on larger numbers of subjects and a wider array of brain tumors

  19. Quantification of Local Tumor Response to Fractionated Radiation Therapy for Non-Hodgkin Lymphoma Using Weekly {sup 18}F-FDG PET/CT Imaging

    SciTech Connect

    Keller, Harald; Goda, Jayant Sastri; Vines, Douglass C.; Lockwood, Gina M.Math.; Tsang, Richard

    2010-03-01

    Purpose: To quantify, in a feasibility study, metabolic and volumetric response to fractionated radiation therapy (RT) using weekly {sup 18}F fluoro-deoxyglucose positron emission tomography (PET) imaging for 10 non-Hodgkin lymphoma (NHL) patients, and to correlate them to clinical outcome. Methods and Materials: Ten patients with chemotherapy-refractory NHL planned for radical RT were prospectively entered into a research study. PET/computed tomography (CT) scans were acquired before RT, and repeated weekly during the 3- to 4-week course of RT, and at 1 and 3 months after therapy. Gross tumor volumes were contoured on CT scans and the corresponding maximum standardized uptake values (SUV{sub max}) determined in the coregistered PET images. The clinical outcomes of interest were local tumor response at 3 months post-RT and local tumor status at last follow-up or time of death. Results: {sup 18}F fluoro-deoxyglucose uptake from inflammation was rarely observed. The responses showed a large variability between patients. SUV{sub max} decreased consistently with a median of -2.1% per Gy (range, -3.3 to -0.7) and the median of the volumetric response was -2.2% per Gy (range, -2.8 to +0.5). Initial SUV{sub max} was not correlated with local control, whereas smaller initial tumor volume was, with smaller tumors more likely to achieve local control. The responses after treatment were also correlated to local control, but not the responses during treatment. Conclusions: Radiation does not confound the FDG uptake in the NHL tumor and normal tissues. Only smaller initial tumor volume and metabolic and volumetric response after completion of radiation therapy significantly correlated with eventual local control.

  20. Computer-assisted framework for machine-learning–based delineation of GTV regions on datasets of planning CT and PET/CT images

    PubMed Central

    Ikushima, Koujiro; Arimura, Hidetaka; Jin, Ze; Yabu-uchi, Hidetake; Kuwazuru, Jumpei; Shioyama, Yoshiyuki; Sasaki, Tomonari; Honda, Hiroshi; Sasaki, Masayuki

    2017-01-01

    We have proposed a computer-assisted framework for machine-learning–based delineation of gross tumor volumes (GTVs) following an optimum contour selection (OCS) method. The key idea of the proposed framework was to feed image features around GTV contours (determined based on the knowledge of radiation oncologists) into a machine-learning classifier during the training step, after which the classifier produces the ‘degree of GTV’ for each voxel in the testing step. Initial GTV regions were extracted using a support vector machine (SVM) that learned the image features inside and outside each tumor region (determined by radiation oncologists). The leave-one-out-by-patient test was employed for training and testing the steps of the proposed framework. The final GTV regions were determined using the OCS method that can be used to select a global optimum object contour based on multiple active delineations with a LSM around the GTV. The efficacy of the proposed framework was evaluated in 14 lung cancer cases [solid: 6, ground-glass opacity (GGO): 4, mixed GGO: 4] using the 3D Dice similarity coefficient (DSC), which denotes the degree of region similarity between the GTVs contoured by radiation oncologists and those determined using the proposed framework. The proposed framework achieved an average DSC of 0.777 for 14 cases, whereas the OCS-based framework produced an average DSC of 0.507. The average DSCs for GGO and mixed GGO were 0.763 and 0.701, respectively, obtained by the proposed framework. The proposed framework can be employed as a tool to assist radiation oncologists in delineating various GTV regions. PMID:27609193

  1. Computer-assisted framework for machine-learning-based delineation of GTV regions on datasets of planning CT and PET/CT images.

    PubMed

    Ikushima, Koujiro; Arimura, Hidetaka; Jin, Ze; Yabu-Uchi, Hidetake; Kuwazuru, Jumpei; Shioyama, Yoshiyuki; Sasaki, Tomonari; Honda, Hiroshi; Sasaki, Masayuki

    2017-01-01

    We have proposed a computer-assisted framework for machine-learning-based delineation of gross tumor volumes (GTVs) following an optimum contour selection (OCS) method. The key idea of the proposed framework was to feed image features around GTV contours (determined based on the knowledge of radiation oncologists) into a machine-learning classifier during the training step, after which the classifier produces the 'degree of GTV' for each voxel in the testing step. Initial GTV regions were extracted using a support vector machine (SVM) that learned the image features inside and outside each tumor region (determined by radiation oncologists). The leave-one-out-by-patient test was employed for training and testing the steps of the proposed framework. The final GTV regions were determined using the OCS method that can be used to select a global optimum object contour based on multiple active delineations with a LSM around the GTV. The efficacy of the proposed framework was evaluated in 14 lung cancer cases [solid: 6, ground-glass opacity (GGO): 4, mixed GGO: 4] using the 3D Dice similarity coefficient (DSC), which denotes the degree of region similarity between the GTVs contoured by radiation oncologists and those determined using the proposed framework. The proposed framework achieved an average DSC of 0.777 for 14 cases, whereas the OCS-based framework produced an average DSC of 0.507. The average DSCs for GGO and mixed GGO were 0.763 and 0.701, respectively, obtained by the proposed framework. The proposed framework can be employed as a tool to assist radiation oncologists in delineating various GTV regions.

  2. Incidental Detection of Femoral Pseudoaneurysm at 18F-FDG PET/CT

    PubMed Central

    Nougaret, Stephanie; Ragucci, Monica; Bach, Ariadne M.; Carollo, Gabriella; Mannelli, Lorenzo

    2016-01-01

    A 72-year-old man with history of lung cancer and melanoma was referred for routine follow-up with 18F-FDG PET/CT. CT images showed a new mass in the right groin associated with mild FDG activity on 18F-FDG PET images. Subsequent ultrasound obtained the same day demonstrated flow within the lesion to be a pseudoaneurysm of the right femoral artery. PMID:26462043

  3. (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.

  4. Functional imaging of interstitial brachytherapy in pancreatic carcinoma xenografts using spectral CT: how does iodine concentration correlate with standardized uptake value of 18FDG-PET-CT?

    PubMed Central

    Hu, Shudong; Shi, Xiaofeng; Chen, Yerong; Huang, Wei; Song, Qi; Lin, Xiaozhu; Liu, Yu; Chen, Kemin

    2016-01-01

    Objective: This study aimed to investigate the correlation between iodine concentration (IC) for the quantitative analysis of spectral CT and maximum standardized uptake value (SUVmax) of 18 fludeoxyglucose positron emission tomography–CT (18FDG PET–CT) as an indicator of therapeutic response to interstitial brachytherapy in transplanted human pancreatic carcinomas in BALB/c-nu mice. Methods: Xenograft models were created by subcutaneous injection of SW1990 human pancreatic cancer cell suspensions into immunodeficient BALB/c-nu mice. 30 mice bearing SW1990 human pancreatic cancer cell xenografts were randomly separated into two groups: experimental (n = 15; 1.0 mCi) and control (n = 15, 0 mCi). After 2 weeks of treatment, spectral CT and 18FDG micro-PET–CT scan were performed. IC values and SUVmax in the lesions were measured. IC normalized to the muscle tissue is indicated as nIC. The relationships between the nIC and SUVmax of the transplantation tumours were analysed. Results: 2 weeks after treatment, the nIC in three-phase scans and SUVmax of the experimental group were significantly lower than those of the control group. The nIC values of the three-phase scans have certain positive correlation with the SUVmax values (r = 0.69, p < 0.05; r = 0.73 and p < 0.05; r = 0.80, p < 0.05 in the 10-, 25- and 60-s phase, respectively). Conclusion: Spectral CT could serve as a valuable imaging modality, as our results suggest that nIC correlates with SUVmax of 18FDG PET–CT for evaluating the therapeutic effect of 125I interstitial brachytherapy in a pancreatic carcinoma xenograft. Advances in knowledge: Spectral CT offers opportunities to assess the therapeutic response of pancreatic cancer. This study supports the conclusion that nIC values in spectral CT could also serve as a valuable functional imaging parameter for early monitoring and evaluation of the therapeutic response of 125I interstitial brachytherapy mouse models

  5. Whole-body MRI including diffusion-weighted MRI compared with 5-HTP PET/CT in the detection of neuroendocrine tumors

    PubMed Central

    Carlbom, Lina; Caballero-Corbalán, José; Granberg, Dan; Sörensen, Jens; Eriksson, Barbro; Ahlström, Håkan

    2017-01-01

    Aim We wanted to explore if whole-body magnetic resonance imaging (MRI) including diffusion-weighted (DW) and liver-specific contrast agent-enhanced imaging could be valuable in lesion detection of neuroendocrine tumors (NET). [11C]-5-Hydroxytryptophan positron emission tomography/computed tomography (5-HTP PET/CT) was used for comparison. Materials and methods Twenty-one patients with NET were investigated with whole-body MRI, including DW imaging (DWI) and contrast-enhanced imaging of the liver, and whole-body 5-HTP PET/CT. Seven additional patients underwent upper abdomen MRI including DWI, liver-specific contrast agent-enhanced imaging, and 5-HTP PET/CT. Results There was a patient-based concordance of 61% and a lesion-based concordance of 53% between the modalities. MRI showed good concordance with PET in detecting bone metastases but was less sensitive in detecting metastases in mediastinal lymph nodes. MRI detected more liver metastases than 5-HTP PET/CT. Conclusion Whole-body MRI with DWI did not detect all NET lesions found with whole-body 5-HTP PET/CT. Our findings indicate that MRI of the liver including liver-specific contrast agent-enhanced imaging and DWI could be a useful complement to whole-body 5-HTP PET/CT. PMID:27894208

  6. A Rationale for the Use of F18-FDG PET/CT in Fever and Inflammation of Unknown Origin

    PubMed Central

    Balink, H.; Verberne, H. J.; Bennink, R. J.; van Eck-Smit, B. L. F.

    2012-01-01

    This review focuses on the diagnostic value of hybrid F18-FDG Positron Emission Tomography/Computerized tomography (PET/CT) in fever of unknown origin (FUO) and inflammation of unknown origin (IUO). Due to the wide range of possible causes both FUO and IUO remain a clinical challenge for both patients and physicians. In addition, the aetiology of IUO shows the same variation in diseases as the FUO spectrum and probably requires the same diagnostic approach as FUO. There are numerous historically used diagnostic approaches incorporating invasive and non-invasive, and imaging techniques, all with relative high specificity but limited sensitivity. This hampers the generalization of these diagnostic approaches. However, recently published reports show that F18-FDG PET/CT in FUO and IUO has a high sensitivity and a relative non-specificity for malignancy, infection and inflammation. This makes F18-FDG PET/CT an ideal diagnostic tool to start the diagnostic process and to guide subsequent focused diagnostic approaches with higher specificity. In addition, F18-FDG PET/CT has a relative high negative predictive value. Therefore F18 FDG PET/CT should be incorporated in the routine diagnostic work-up of patients with FUO and IUO, preferably at an early stage in the diagnostic process. PMID:23316356

  7. Molecular imaging of active mutant L858R EGF receptor (EGFR) kinase-expressing nonsmall cell lung carcinomas using PET/CT.

    PubMed

    Yeh, Hsin Hsien; Ogawa, Kazuma; Balatoni, Julius; Mukhapadhyay, Uday; Pal, Asutosh; Gonzalez-Lepera, Carlos; Shavrin, Aleksandr; Soghomonyan, Suren; Flores, Leo; Young, Daniel; Volgin, Andrei Y; Najjar, Amer M; Krasnykh, Victor; Tong, William; Alauddin, Mian M; Gelovani, Juri G

    2011-01-25

    The importance of the EGF receptor (EGFR) signaling pathway in the development and progression of nonsmall cell lung carcinomas (NSCLC) is widely recognized. Gene sequencing studies revealed that a majority of tumors responding to EGFR kinase inhibitors harbor activating mutations in the EGFR kinase domain. This underscores the need for novel biomarkers and diagnostic imaging approaches to identify patients who may benefit from particular therapeutic agents and approaches with improved efficacy and safety profiles. To this goal, we developed 4-[(3-iodophenyl)amino]-7-{2-[2-{2-(2-[2-{2-([(18)F]fluoroethoxy)-ethoxy}-ethoxy]-ethoxy)-ethoxy}-ethoxy]-quinazoline-6-yl-acrylamide ([(18)F]F-PEG6-IPQA), a radiotracer with increased selectivity and irreversible binding to the active mutant L858R EGFR kinase. We show that PET with [(18)F]F-PEG6-IPQA in tumor-bearing mice discriminates H3255 NSCLC xenografts expressing L858R mutant EGFR from H441 and PC14 xenografts expressing EGFR or H1975 xenografts with L858R/T790M dual mutation in EGFR kinase domain, which confers resistance to EGFR inhibitors (i.e., gefitinib). The T790M mutation precludes the [(18)F]F-PEG6-IPQA from irreversible binding to EGFR. These results suggest that PET with [(18)F]F-PEG6-IPQA could be used for the selection of NSCLC patients for individualized therapy with small molecular inhibitors of EGFR kinase that are currently used in the clinic and have a similar structure (i.e., iressa, gefitinib, and erlotinib).

  8. Somatostatin receptor based PET/CT in patients with the suspicion of cardiac sarcoidosis: an initial comparison to cardiac MRI.

    PubMed

    Lapa, Constantin; Reiter, Theresa; Kircher, Malte; Schirbel, Andreas; Werner, Rudolf A; Pelzer, Theo; Pizarro, Carmen; Skowasch, Dirk; Thomas, Lena; Schlesinger-Irsch, Ulrike; Thomas, Daniel; Bundschuh, Ralph A; Bauer, Wolfgang R; Gärtner, Florian C

    2016-11-22

    Diagnosis of cardiac sarcoidosis is often challenging. Whereas cardiac magnetic resonance imaging (CMR) and positron emission tomography/computed tomography (PET/CT) with 18F-fluorodeoxyglucose (FDG) are most commonly used to evaluate patients, PET/CT using radiolabeled somatostatin receptor (SSTR) ligands for visualization of inflammation might represent a more specific alternative. This study aimed to investigate the feasibility of SSTR-PET/CT for detecting cardiac sarcoidosis in comparison to CMR.15 patients (6 males, 9 females) with sarcoidosis and suspicion on cardiac involvement underwent SSTR-PET/CT imaging and CMR. Images were visually scored. The AHA 17-segment model of the left myocardium was used for localization and comparison of inflamed myocardium for both imaging modalities. In semi-quantitative analysis, mean (SUVmean) and maximum standardized uptake values (SUVmax) of affected myocardium were calculated and compared with both remote myocardium and left ventricular (LV) cavity.SSTR-PET was positive in 7/15, CMR in 10/15 patients. Of the 3 CMR+/PET- subjects, one patient with minor involvement (<25% of wall thickness in CMR) was missed by PET. The remaining two CMR+/PET- patients displayed no adverse cardiac events during follow-up.In the 17-segment model, PET/CT yielded 27 and CMR 29 positive segments. Overall concordance of the 2 modalities was 96.1% (245/255 segments analyzed). SUVmean and SUVmax in inflamed areas were 2.0±1.2 and 2.6±1.2, respectively. The lesion-to-remote myocardium and lesion-to-LV cavity ratios were 1.8±0.2 and 1.9±0.2 for SUVmean and 2.0±0.3 and 1.7±0.3 for SUVmax, respectively.Detection of cardiac sarcoidosis by SSTR-PET/CT is feasible. Our data warrant further analysis in larger prospective series.

  9. Somatostatin receptor based PET/CT in patients with the suspicion of cardiac sarcoidosis: an initial comparison to cardiac MRI

    PubMed Central

    Kircher, Malte; Schirbel, Andreas; Werner, Rudolf A.; Pelzer, Theo; Pizarro, Carmen; Skowasch, Dirk; Thomas, Lena; Schlesinger-Irsch, Ulrike; Thomas, Daniel; Bundschuh, Ralph A.

    2016-01-01

    Diagnosis of cardiac sarcoidosis is often challenging. Whereas cardiac magnetic resonance imaging (CMR) and positron emission tomography/computed tomography (PET/CT) with 18F-fluorodeoxyglucose (FDG) are most commonly used to evaluate patients, PET/CT using radiolabeled somatostatin receptor (SSTR) ligands for visualization of inflammation might represent a more specific alternative. This study aimed to investigate the feasibility of SSTR–PET/CT for detecting cardiac sarcoidosis in comparison to CMR. 15 patients (6 males, 9 females) with sarcoidosis and suspicion on cardiac involvement underwent SSTR-PET/CT imaging and CMR. Images were visually scored. The AHA 17-segment model of the left myocardium was used for localization and comparison of inflamed myocardium for both imaging modalities. In semi-quantitative analysis, mean (SUVmean) and maximum standardized uptake values (SUVmax) of affected myocardium were calculated and compared with both remote myocardium and left ventricular (LV) cavity. SSTR-PET was positive in 7/15, CMR in 10/15 patients. Of the 3 CMR+/PET− subjects, one patient with minor involvement (<25% of wall thickness in CMR) was missed by PET. The remaining two CMR+/PET− patients displayed no adverse cardiac events during follow-up. In the 17-segment model, PET/CT yielded 27 and CMR 29 positive segments. Overall concordance of the 2 modalities was 96.1% (245/255 segments analyzed). SUVmean and SUVmax in inflamed areas were 2.0±1.2 and 2.6±1.2, respectively. The lesion-to-remote myocardium and lesion-to-LV cavity ratios were 1.8±0.2 and 1.9±0.2 for SUVmean and 2.0±0.3 and 1.7±0.3 for SUVmax, respectively. Detection of cardiac sarcoidosis by SSTR-PET/CT is feasible. Our data warrant further analysis in larger prospective series. PMID:27780922

  10. Dosimetry of patients submitted to cerebral PET/CT for the diagnosis of mild cognitive impairment

    PubMed Central

    Santana, Priscila do Carmo; Mourão, Arnaldo Prata; de Oliveira, Paulo Márcio Campos; Bernardes, Felipe Dias; Mamede, Marcelo; da Silva, Teógenes Augusto

    2014-01-01

    Objective The present study was aimed at evaluating the effective radiation dose in patients submitted to PET/CT for the diagnosis of mild cognitive impairment. Materials and Methods TLD-100 detectors inserted into an Alderson Rando® anthropomorphic phantom were utilized to measure the absorbed dose coming from the CT imaging modality. The anthropomorphic phantoms (male and female adult versions) were submitted to the same technical protocols for patients’ images acquisition. The absorbed dose resulting from the radiopharmaceutical injection was estimated by means of the model proposed by the ICRP publication 106. Results The effective dose in patients submitted to this diagnostic technique was approximately (5.34 ± 1.99) mSv. Conclusion Optimized protocols for calculation of radioactive activity injected into patients submitted to this diagnostic technique might contribute to reduce the effective radiation dose resulting from PET/CT in the diagnosis of mild cognitive impairment. PMID:25741117

  11. Early Detection of Bilateral Testicular Metastases From Prostatic Adenocarcinoma Using 68Ga-PSMA Ligand PET/CT.

    PubMed

    Weiberg, Desiree; Radner, Herbert; Derlin, Thorsten; Thon, Walter F

    2017-03-31

    We present the case of a 76-year-old man with biochemical relapse after primary therapy for prostate cancer. Ga prostate-specific membrane antigen (PSMA) ligand PET/CT performed for localization of recurrent disease revealed bilateral metastases to the testes. Histopathologic evaluation after bilateral orchiectomy revealed testicular metastases. Metastases to the testes are rare and usually seen in advanced stages. Ga-PSMA ligand PET/CT is a highly sensitive and specific imaging method for the detection of primary and metastatic prostate cancer and has refined diagnostic approaches. This case highlights the potential of PSMA-targeted PET/CT for detection of prostate cancer metastases, even in very unusual localizations.

  12. Uptake of an Acrochordon Incidentally Detected on 68Ga Prostate-Specific Membrane Antigen PET/CT.

    PubMed

    Daglioz Gorur, Gozde; Hekimsoy, Turkay; Isgoren, Serkan; Sikar Akturk, Aysun; Demir, Hakan

    2017-03-31

    Ga prostate-specific membrane antigen (PSMA) PET/CT is a promising tool for imaging of prostate cancer. Ga-PSMA PET/CT uptake of prostate cancer and its metastases are reflective of significant overexpression of PSMA. However, PSMA expression of benign neoplasms and nonprostate epithelial malignancies is not very well defined. We report a moderate Ga-PSMA uptake of an acrochordon (skin tag), which was incidentally found in a patient referred for staging prostate cancer. Acrochordon is a frequent, small, soft, skin-colored or hyperpigmented, benign, and usually pedunculated neoplasm of the skin. Nuclear medicine physicians should be aware of it while reporting a Ga-PSMA PET/CT.

  13. Ultra-low dose CT attenuation correction for PET/CT

    NASA Astrophysics Data System (ADS)

    Xia, Ting; Alessio, Adam M.; De Man, Bruno; Manjeshwar, Ravindra; Asma, Evren; Kinahan, Paul E.

    2012-01-01

    A challenge for positron emission tomography/computed tomography (PET/CT) quantitation is patient respiratory motion, which can cause an underestimation of lesion activity uptake and an overestimation of lesion volume. Several respiratory motion correction methods benefit from longer duration CT scans that are phase matched with PET scans. However, even with the currently available, lowest dose CT techniques, extended duration cine CT scans impart a substantially high radiation dose. This study evaluates methods designed to reduce CT radiation dose in PET/CT scanning. We investigated selected combinations of dose reduced acquisition and noise suppression methods that take advantage of the reduced requirement of CT for PET attenuation correction (AC). These include reducing CT tube current, optimizing CT tube voltage, adding filtration, CT sinogram smoothing and clipping. We explored the impact of these methods on PET quantitation via simulations on different digital phantoms. CT tube current can be reduced much lower for AC than that in low dose CT protocols. Spectra that are higher energy and narrower are generally more dose efficient with respect to PET image quality. Sinogram smoothing could be used to compensate for the increased noise and artifacts at radiation dose reduced CT images, which allows for a further reduction of CT dose with no penalty for PET image quantitation. When CT is not used for diagnostic and anatomical localization purposes, we showed that ultra-low dose CT for PET/CT is feasible. The significant dose reduction strategies proposed here could enable respiratory motion compensation methods that require extended duration CT scans and reduce radiation exposure in general for all PET/CT imaging.

  14. Incidentally Detected Agenesis of Dorsal Pancreas on PET/CT: Case Report and Review of Literature

    PubMed Central

    Kabnurkar, Rasika; Rokade, M L; Bandekar, Kalashree; Kamat, Nikhil

    2017-01-01

    Agenesis of Dorsal Pancreas (ADP) is a rare congenital anomaly characterized by the absence of body and tail of pancreas. We report a case of incidentally detected ADP on Contrast Enhanced Computed Tomography (CECT) component of Fluorodeoxyglucose Positron Emission Tomography (FDG PET/CT) in a treated case of carcinoma (Ca) tongue with suspected local recurrence. Dependent Intestine Sign, hallmark of ADP on CECT imaging was noted in our patient. PMID:28242982

  15. The Utility of 68Ga-PSMA PET/CT in Poorly Differentiated Metastatic Prostate Cancer.

    PubMed

    Demirkol, Mehmet Onur; Kiremit, Murat Can; Acar, Omer; Ucar, Burcu; Saglican, Yesim

    2017-03-17

    We aimed to emphasize how useful PSMA PET/CT findings can be while trying to restage prostate cancer after radical prostatectomy in the presence of low prostate-specific antigen values. A 64-year-old man with pT3b N1 M0 Gleason 7 adenocarcinoma of the prostate presented 5 years postoperatively with a palpable axillary mass, whereas his prostate-specific antigen was 0.08 ng/mL. Conventional imaging studies and histopathologic findings of the axillary mass biopsy revealed inconclusive results. Ga-PSMA PET/CT demonstrated PSMA-positive metastatic lesions, the largest one being located in the right axilla. This finding confirmed metastatic poorly differentiated prostate cancer, and androgen deprivation therapy was initiated.

  16. Newer PET application with an old tracer: role of 18F-NaF skeletal PET/CT in oncologic practice.

    PubMed

    Bastawrous, Sarah; Bhargava, Puneet; Behnia, Fatemeh; Djang, David S W; Haseley, David R

    2014-01-01

    The skeleton is one of the most common sites for metastatic disease, particularly from breast and prostate cancer. Bone metastases are associated with considerable morbidity, and accurate imaging of the skeleton is important in determining the appropriate therapeutic plan. Sodium fluoride labeled with fluorine 18 (sodium fluoride F 18 [(18)F-NaF]) is a positron-emitting radiopharmaceutical first introduced several decades ago for skeletal imaging. (18)F-NaF was approved for clinical use as a positron emission tomographic (PET) agent by the U.S. Food and Drug Administration in 1972. The early use of this agent was limited, given the difficulties of imaging its high-energy photons on the available gamma cameras. For skeletal imaging, it was eventually replaced by technetium 99m ((99m)Tc)-labeled agents because of the technical limitations of (18)F-NaF. During the past several years, the widespread availability and implementation of hybrid PET and computed tomographic (CT) dual-modality systems (PET/CT) have encouraged a renewed interest in (18)F-NaF PET/CT for routine clinical use in bone imaging. Because current PET/CT systems offer high sensitivity and spatial resolution, the use of (18)F-NaF has been reevaluated for the detection of malignant and nonmalignant osseous disease. Growing evidence suggests that (18)F-NaF PET/CT provides increased sensitivity and specificity in the detection of bone metastases. Furthermore, the favorable pharmacokinetics of (18)F-NaF, combined with the superior imaging characteristics of PET/CT, supports the routine clinical use of (18)F-NaF PET/CT for oncologic imaging for skeletal metastases. In this article, a review of the indications, imaging appearances, and utility of (18)F-NaF PET/CT in the evaluation of skeletal disease is provided, with an emphasis on oncologic imaging.

  17. False-positive FDG PET uptake--the role of PET/CT.

    PubMed

    Rosenbaum, Sandra J; Lind, Thomas; Antoch, Gerald; Bockisch, Andreas

    2006-05-01

    Positron emission tomography (PET) is a powerful molecular imaging technique for the human body-imaging applications currently available. As altered glucose metabolism is characteristic for many malignancies, FDG-PET is mostly used in oncology for staging and therapy control. Although PET is a sensitive tool for detecting malignancy, FDG uptake is not tumor specific. It can also be seen in healthy tissue or in benign disease as inflammation or posttraumatic repair and could be mistaken for cancer. The experienced nuclear medicine physician mostly manages to differentiate malignant from non-malignant FDG uptake, but some findings may remain ambiguous. In these cases, the difficulties in differentiating physiologic variants or benign causes of FDG uptake from tumor tissue can often be overcome by combined PET and CT (PET/CT) as anatomic information is added to the metabolic data. Thus, PET/CT improves the diagnostic accuracy compared to PET alone and helps to avoid unnecessary surgery/therapy. However, PET/CT involves other sources of artifacts that may occur when using CT for attenuation correction of PET or by patient motion caused by respiration or bowel movements.

  18. PET/CT alignment calibration with a non-radioactive phantom and the intrinsic 176Lu radiation of PET detector

    NASA Astrophysics Data System (ADS)

    Wei, Qingyang; Ma, Tianyu; Wang, Shi; Liu, Yaqiang; Gu, Yu; Dai, Tiantian

    2016-11-01

    Positron emission tomography/computed tomography (PET/CT) is an important tool for clinical studies and pre-clinical researches which provides both functional and anatomical images. To achieve high quality co-registered PET/CT images, alignment calibration of PET and CT scanner is a critical procedure. The existing methods reported use positron source phantoms imaged both by PET and CT scanner and then derive the transformation matrix from the reconstructed images of the two modalities. In this paper, a novel PET/CT alignment calibration method with a non-radioactive phantom and the intrinsic 176Lu radiation of the PET detector was developed. Firstly, a multi-tungsten-alloy-sphere phantom without positron source was designed and imaged by CT and the PET scanner using intrinsic 176Lu radiation included in LYSO. Secondly, the centroids of the spheres were derived and matched by an automatic program. Lastly, the rotation matrix and the translation vector were calculated by least-square fitting of the centroid data. The proposed method was employed in an animal PET/CT system (InliView-3000) developed in our lab. Experimental results showed that the proposed method achieves high accuracy and is feasible to replace the conventional positron source based methods.

  19. Evaluation of 18-F-fluoro-2-deoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) as a staging and monitoring tool for dogs with stage-2 splenic hemangiosarcoma – A pilot study

    PubMed Central

    Winter, Amber L.; Stuebner, Kathleen; Scott, Ruth; Ober, Christopher P.; Anderson, Kari L.; Feeney, Daniel A.; Vallera, Daniel A.; Koopmeiners, Joseph S.; Modiano, Jaime F.; Froelich, Jerry

    2017-01-01

    Positron Emission Tomography-Computed Tomography (PET-CT) is routinely used for staging and monitoring of human cancer patients and is becoming increasingly available in veterinary medicine. In this study, 18-fluorodeoxyglucose (18FDG)-PET-CT was used in dogs with naturally occurring splenic hemangiosarcoma (HSA) to assess its utility as a staging and monitoring modality as compared to standard radiography and ultrasonography. Nine dogs with stage-2 HSA underwent 18FDG-PET-CT following splenectomy and prior to commencement of chemotherapy. Routine staging (thoracic radiography and abdominal ultrasonography) was performed prior to 18FDG-PET-CT in all dogs. When abnormalities not identified on routine tests were noted on 18FDG-PET-CT, owners were given the option to repeat a PET-CT following treatment with eBAT. A PET-CT scan was repeated on Day 21 in three dogs. Abnormalities not observed on conventional staging tools, and most consistent with malignant disease based on location, appearance, and outcome, were detected in two dogs and included a right atrial mass and a hepatic nodule, respectively. These lesions were larger and had higher metabolic activity on the second scans. 18FDG-PET-CT has potential to provide important prognostic information and influence treatment recommendations for dogs with stage-2 HSA. Additional studies will be needed to precisely define the value of this imaging tool for staging and therapy monitoring in dogs with this and other cancers. PMID:28222142

  20. Herniation pit mimicking osseous metastasis on 18F-FDG PET/CT in patient with lung cancer.

    PubMed

    Yoo, Su Woong; Song, Ho-Chun; Oh, Jong-Ryool; Kim, Jahae; Kang, Sae-Ryung; Chong, Ari; Byun, Byung Hyun; Hong, Sun-Pyo; Min, Jung-Joon; Bom, Hee-Seung

    2012-07-01

    Herniation pits are small subcortical osseous defects located typically at the proximal anterosuperior quadrant of the femoral neck that are most frequently seen in the young, athletic adult population. We report a case with herniation pit showing focal 18F-FDG uptake on PET/CT images mimicking osseous metastasis in a 69-year-old patient with lung cancer.

  1. Adenocarcinoma of the Cervix Uteri and Endometrium Combined With the Kartagener Syndrome on FDG PET/CT.

    PubMed

    Zhang, Yin; Chen, Yue; Huang, Zhanwen; Zhou, Fan

    2015-11-01

    A 45-year-old woman with pathologically confirmed adenocarcinoma of the cervix uteri and endometrium underwent FDG PET/CT for staging. No metastasis was found. However, the images revealed bronchiectasis, sinusitis, and situs inversus totalis, which are the triad of Kartagener syndrome.

  2. Radionecrosis versus disease progression in brain metastasis. Value of (18)F-DOPA PET/CT/MRI.

    PubMed

    Hernández Pinzón, J; Mena, D; Aguilar, M; Biafore, F; Recondo, G; Bastianello, M

    2016-01-01

    The use of (18)F-DOPA PET/CT with magnetic resonance imaging fusion and the use of visual methods and quantitative analysis helps to differentiate between changes post-radiosurgery vs. suspicion of disease progression in a patient with brain metastases from melanoma, thus facilitating taking early surgical action.

  3. 18-FDG PET/CT assessment of basal cell carcinoma with vismodegib.

    PubMed

    Thacker, Curtis A; Weiss, Glen J; Tibes, Raoul; Blaydorn, Lisa; Downhour, Molly; White, Erica; Baldwin, Jason; Hoff, Daniel D; Korn, Ronald L

    2012-10-01

    The use of 18-fluorodeoxyglucose (FDG) positron emission tomography with computed tomography (PET/CT) in subjects with advanced basal cell carcinoma (BCC) has not been fully explored due to the rarity of disease presentation. This study evaluated PET/CTs from subjects with advanced BCC participating in a phase I dose-escalation clinical trial of vismodegib. Fourteen subjects with BCC were imaged with 18-FDG PET/CT for lesion identification and response categorizing (European Organisation for Research and Treatment for Cancer [EORTC] and PET response criteria in solid tumors [PERCIST] 1.0). Several parameters including metabolic activity of target lesions, site of disease presentation and spread, treatment response, and prognostic significance of metabolic activity following therapy were evaluated. All subjects exhibited at least one hypermetabolic lesion. Most subjects had only four organ systems involved at study enrollment: skin-muscle (93%), lung (57%), lymph nodes (29%), and bone (21%). SUVmax measured across all lesions decreased (median 33%, SD ± 45%) following therapy with metabolic activity normalizing or disappearing in 42% of lesions. No significant difference was observed between EORTC and PERCIST 1.0. Subjects that demonstrated at least a 33% reduction in SUVmax from baseline had a significantly longer progression-free survival (PFS) (median 17 months, 95% confidence interval [CI] ±4 months vs. 9 months, 95% CI ±5 months, P = 0.038) and overall survival (OS) (median 24 months, 95% CI ±4 months vs. 17 months, 95% CI ±13 months, P = 0.019). BCC lesions are hypermetabolic on 18-FDG PET/CT. A decrease in SUVmax was associated with improved PFS and OS. These results further support the incorporation of 18-FDG PET/CT scans in advanced BCC management.

  4. PET-CT Fusion in Radiation Management of Patients with Anorectal Tumors

    SciTech Connect

    Anderson, Cynthia; Koshy, Mary; Staley, Charles; Esiashvili, Natia; Ghavidel, Sharam; Fowler, Zach; Fox, Tim; Esteves, Fabio; Landry, Jerome Godette, Karen

    2007-09-01

    Purpose: To compare computed tomography (CT) with positron emission tomography-CT (PET-CT) scans with respect to anorectal tumor volumes, correlation in overlap, and influence on radiation treatment fields and patient care. Patients and Methods: From March to November 2003, 20 patients with rectal cancer and 3 patients with anal cancer were treated with preoperative or definitive chemoradiation, respectively. Computed tomography simulation data generated a CT gross tumor volume (CT-GTV) and CT planning target volume (CT-PTV) and {sup 18}F-fluoro-2-deoxy-glucose PET (FDG-PET) created a PET-GTV and PET-PTV. The PET-CT and CT images were fused using manual coregistration. Patients were treated with three-dimensional conformal therapy to traditional doses. The PET, CT, and overlap volumes (OVs) were measured in cubic centimeters. Results: Mean PET-GTV was smaller than the mean CT-GTV (91.7 vs. 99.6 cm{sup 3}). The mean OV was 46.7%. As tumor volume increased, PET and CT OV correlated significantly (p < 0.001). In 17% of patients PET-CT altered the PTV, and in 26% it changed the radiation treatment plan. For 25% of patients with rectal cancer, PET detected distant metastases and changed overall management. Ten rectal cancer patients underwent surgery. When the pretreatment PET standardized uptake value was >10 and the posttreatment PET standardized uptake value was <6, 100% achieved pathologic downstaging (p = 0.047). Conclusions: Variation in volume was significant, with 17% and 26% of patients requiring a change in treatment fields and patient management, respectively. Positron emission tomography can change the management for anorectal tumors by early detection of metastatic disease or disease outside standard radiation fields.

  5. A rib-specific multimodal registration algorithm for fused unfolded rib visualization using PET/CT

    NASA Astrophysics Data System (ADS)

    Kaftan, Jens N.; Kopaczka, Marcin; Wimmer, Andreas; Platsch, Günther; Declerck, Jérôme

    2014-03-01

    Respiratory motion affects the alignment of PET and CT volumes from PET/CT examinations in a non-rigid manner. This becomes particularly apparent if reviewing fine anatomical structures such as ribs when assessing bone metastases, which frequently occur in many advanced cancers. To make this routine diagnostic task more efficient, a fused unfolded rib visualization for 18F-NaF PET/CT is presented. It allows to review the whole rib cage in a single image. This advanced visualization is enabled by a novel rib-specific registration algorithm that rigidly optimizes the local alignment of each individual rib in both modalities based on a matched filter response function. More specifically, rib centerlines are automatically extracted from CT and subsequently individually aligned to the corresponding bone-specific PET rib uptake pattern. The proposed method has been validated on 20 PET/CT scans acquired at different clinical sites. It has been demonstrated that the presented rib- specific registration method significantly improves the rib alignment without having to run complex deformable registration algorithms. At the same time, it guarantees that rib lesions are not further deformed, which may otherwise affect quantitative measurements such as SUVs. Considering clinically relevant distance thresholds, the centerline portion with good alignment compared to the ground truth improved from 60:6% to 86:7% after registration while approximately 98% can be still considered as acceptably aligned.

  6. An atypical sarcoidosis involvement in FDG PET/CT

    PubMed Central

    Robin, Philippe; Benigni, Paolo; Feger, Benoit; Salaun, Pierre-Yves; Abgral, Ronan

    2016-01-01

    Abstract Rationale: Sarcoidosis is an idiopathic systemic inflammatory granulomatous disorder comprised of epithelioid and multinucleated giant cells with little necrosis which involve various organs. Laryngeal involvement is extremely rare, with a prevalence of about 0.5 to 1%. Diagnoses: Here we present a case of laryngeal involvement of sarcoidosis demonstrated on 18F-Fluorodesoxyglucose Positron-Emission Tomography/Computed Tomography (FDG PET/CT). Patient concerns: A 63 year-old man suffering from dysphonia was referred to our department for characterization of laryngeal lesion suspicious for cancer with non-informative biopsy, the sample was not sufficient for diagnosis. Interventions: FDG PET/CT showed a pathological uptake on the right vocal cord, but also highlighted a bilateral uptake in intrathoracic hilar lymphadenopathy areas, typically found in several inflammatory diseases. Outcomes: New laryngeal targeted biopsies revealed non-caseating epithelioid granulomas suggesting sarcoidosis involvement. After 6 months of systemic steroid treatment, FDG PET/CT showed a significant decrease of the laryngeal uptake. Lessons: This case shows the usefulness of FDG PET/CT to accurately assess inflammatory activity in rare extra-pulmonary sarcoidosis involvement. Moreover, this case emphasizes that FDG PET/CT is an interesting tool for assessing therapeutic efficacy of inflammatory diseases such as sarcoidosis. PMID:28033265

  7. TU-A-18A-01: Basic Principles of PET/CT, Calibration Methods and Contrast Recovery Across Multiple Cameras

    SciTech Connect

    Kappadath, S; Nye, J

    2014-06-15

    This continuing education session will discuss the physical principles of PET/CT imaging and characterization of contrast recovery using accreditation phantoms. A detailed overview will be given on the physical principles of PET including positron decay physics, 2D and 3D data acquisition, time-of-flight, scatter correction, CT attenuation correction, and image reconstruction. Instrument quality control and calibration procedures will be discussed. Technical challenges, common image artifacts and strategies to mitigate these issues will also be discussed. Data will be presented on acquisition techniques and reconstruction parameters affecting contrast recovery. The discussion will emphasize the minimization of reconstruction differences in quantification metrics such as SUV and contrast recovery coefficients for the NEMA and ACR clinical trial phantoms. Data from new and older generation scanners will be shown including comparison of contrast recovery measurements to their analytical solutions. The goal of this session is to update attendees on the quality control and calibration of PET/CT scanners, on methods to establish a common calibration for PET/CT scanners to control for instrument variance across multiple sites. Learning Objectives: Review the physical principles of PET/CT, quality control and calibration Gain further understanding on how to apply techniques for improving quantitative agreement across multiple cameras Describe the differences between measured and expected contrast recovery for the NEMA and ACR PET phantoms.

  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. Diagnostic Value of (18)F-FDG PET/CT versus MRI in the Setting of Antibody Specific Autoimmune Encephalitis.

    PubMed

    Solnes, Lilja B; Jones, Krystyna M; Rowe, Steven P; Pattanayak, Puskar; Nalluri, Abhinav; Venkatesan, Arun; Probasco, John C; Javadi, Mehrbod Som

    2017-02-16

    Introduction: Diagnosis of autoimmune encephalitis presents some challenges in the clinical setting due to varied clinical presentations and delay in obtaining antibody panel results. We examined the role of neuroimaging in the setting of autoimmune encephalitides comparing the utility (18)F-FDG PET/CT versus conventional brain imaging with MRI. Methods: A retrospective study was performed assessing the positivity rate of MRI versus (18)F-FDG PET/CT during the initial work-up of 23 patients proven to have antibody positive autoimmune encephalitis. (18)F-FDG PET/CT studies were analyzed qualitatively and using Cortex ID (GE Health systems). Areas of cortical lobar hypo (hyper) metabolism in the cerebrum that were 2 standard deviations from the mean were recorded as abnormal. Results: On visual inspection, all patients were identified to have abnormal pattern of (18)F-FDG uptake. In semi-quantitative analysis at least one region of interest with metabolic change was identified in 22/23 (95.6%) patients using discriminating Z-score of 2. Overall, (18)F-FDG PET/CT was more often abnormal during the diagnostic period than MRI (10/23, 43% of patients). The predominant finding on brain (18)F-FDG PET/CT imaging was lobar hypometabolism, being observed in 21/23 (91.3%) of patients. Hypometabolism were most commonly observed in parietal lobe following by occipital lobe. An entire subset of antibody positive patients, anti-NMDAR (5 patients), had normal MRIs and abnormal (18)F-FDG PET/CT while other subsets demonstrated a greater heterogeneity. Conclusion: Brain (18)F-FDG PET/CT may play a significant role in initial evaluation of patients with clinically suspected antibody-mediated autoimmune encephalitis. Given that it is more often abnormal when compared with MRI in the acute setting, this molecular imaging technique may be better positioned as an early biomarker of disease so that treatment may be initiated earlier resulting in improved patient outcomes.

  10. Intra-abdominal desmoplastic small round cell tumors: CT and FDG-PET/CT findings with histopathological association.

    PubMed

    Chen, Jingjing; Wu, Zengjie; Sun, Binbin; Li, Dacheng; Wang, Zhenguang; Liu, Fangjun; Hua, Hui

    2016-05-01

    Desmoplastic small round cell tumors (DSRCTs) are rare and aggressive malignant tumors. The aim of the present study was to analyze computed tomography (CT) and fluorodeoxyglucose positron emission tomography (FDG-PET)/CT imaging features of intra-abdominal desmoplastic DSRCT, and investigate the association of these features with histopathological results. The present study was a retrospective investigation of 4 patients with DSRCT. All patients underwent CT and dynamic CT, and 1 additionally underwent FDG-PET/CT scanning. Following a tumor resection, routine hematoxylin and eosin staining, and immunostaining, were performed and evaluated. Multiple large abdominopelvic masses were identified in all 4 patients; however, no indications of their site of origin were demonstrated. CT revealed soft-tissue masses with patchy foci of hypodense lesions. Contrast-enhanced CT revealed slightly or moderately heterogeneous enhancement of the lesions. Other observations from these patients included calcification (n=2), peritoneal seeding (n=3), hepatic metastasis (n=3), retroperitoneal lymphadenopathy (n=3) and ascites (n=2). FDG-PET/CT revealed multiple nodular increased FDG uptake in the abdominopelvic masses, and in the liver and peritoneum in 1 case. Intra-abdominal DSRCT demonstrated significant diagnostic characteristics on plain and contrast-enhanced CT. Multiple, bulky soft-tissue masses inside the peritoneal cavity, particularly in male adolescents and young adults, should be considered as potential cases of DSRCT. FDG-PET/CT techniques may be utilized to aid the staging of tumors.

  11. 18F-FDG PET/CT and extragastric MALT lymphoma: role of Ki-67 score and plasmacytic differentiation.

    PubMed

    Albano, Domenico; Bosio, Giovanni; Giubbini, Raffaele; Bertagna, Francesco

    2017-03-07

    The detection rate of fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) in extragastric mucosa associated lymphoid tissue (MALT) lymphoma is under debate and the reason is not clear. Our aim was to investigate the metabolic behavior of extragastric MALT lymphoma and whether the histological features (Ki-67 index and plasmacytic differentiation, PD) might explain it. PET/CT images were analyzed visually and semi-quantitatively and compared with Ki-67 index and PD. Seventy-two patients were included. Twelve of 18 patients with PD showed intense 18F-FDG uptake; on the contrary, 42 of 54 patients without PD had positive 18F-FDG PET/CT. Twenty-six of 27 patients with Ki-67 > 15% had 18F-FDG-avid lesions; 28 of 45 patients with Ki-67 ≤ 15% had positive 18F-FDG PET/CT. 18F-FDG avidity was significantly associated with Ki-67 index (p < .001) and not correlated with PD (p = .352). Maximum standardized uptake value (SUVmax), lesion-to-liver SUVmax ratio and lesion-to-blood pool SUVmax ratio were not correlated with Ki-67 index or PD. 18F-FDG avidity was noted in 75% and is correlated only with Ki-67.

  12. The Role of [18F]FDG-PET/CT in Predicting Malignant Transformation of Plexiform Neurofibromas in Neurofibromatosis-1

    PubMed Central

    Abdul Razak, Muzib; London, Kevin

    2016-01-01

    Background. Malignant peripheral nerve sheath tumours (MPNSTs) are difficult to diagnose and treat and contribute to significant morbidity and mortality for patients with Neurofibromatosis-1 (NF-1). FDG-PET/CT is being increasingly used as an imaging modality to discriminate between benign and malignant plexiform neurofibromas. Objectives. To assess the value of FDG-PET/CT in differentiating between benign and malignant peripheral nerve lesions for patients with Neurofibromatosis-1. Methods. A systematic review of the literature was performed prior to application of stringent selection criteria. Ultimately 13 articles with 796 tumours were deemed eligible for inclusion into the review. Results. There was a significant difference between mean SUVmax of benign and malignant lesions (1.93 versus 7.48, resp.). Sensitivity ranged from 89 to 100% and specificity from 72 to 94%. ROC analysis was performed to maximise sensitivity and specificity of SUVmax cut-off; however no clear value was identified (range 3.1–6.1). Significant overlap was found between the SUVmax of benign and malignant lesions making differentiation of lesions difficult. Many of the studies suffered from having a small cohort and from not providing histological data on all lesions which underwent FDG-PET/CT. Conclusion. This systematic review is able to demonstrate that FDG-PET/CT is a useful noninvasive test for discriminating between benign and malignant lesions but has limitations and requires further prospective trials. PMID:28058117

  13. PET/CT surveillance detects asymptomatic recurrences in stage IIIB and IIIC melanoma patients: a prospective cohort study.

    PubMed

    Madu, Max F; Timmerman, Pieter; Wouters, Michel W J M; van der Hiel, Bernies; van der Hage, Jos A; van Akkooi, Alexander C J

    2017-02-20

    AJCC stage IIIB and IIIC melanoma patients are at risk for disease relapse or progression. The advent of effective systemic therapies has made curative treatment of progressive disease a possibility. As resection of oligometastatic disease can confer a survival benefit and as immunotherapy is possibly most effective in a low tumor load setting, there is a likely benefit to early detection of progression. The aim of this pilot study was to evaluate a PET/computed tomography (CT) surveillance schedule for resected stage IIIB and IIIC melanoma. From 1-2015, stage IIIB and IIIC melanoma patients at our institution underwent 6-monthly surveillance with PET/CT, together with 3-monthly S100B assessment. When symptoms or elevated S100B were detected, an additional PET/CT was performed. Descriptive statistics were used to evaluate outcomes for this surveillance schedule. Fifty-one patients were followed up, 27 patients developed a recurrence before surveillance imaging, five were detected by an elevated S100B, and one patient was not scanned according to protocol. Eighteen patients were included. Thirty-two scans were acquired. Eleven relapses were suspected on PET/CT. Ten scans were true positive, one case was false positive, and one case was false negative. All recurrences detected by PET/CT were asymptomatic at that time, with a normal range of S100B. The number of scans needed to find one asymptomatic relapse was 3.6. PET/CT surveillance imaging seems to be an effective strategy for detecting asymptomatic recurrence in stage IIIB and IIIC melanoma patients in the first year after complete surgical resection.

  14. Breast implant foreign body reaction mimicking breast cancer recurrence on FDG PET/CT.

    PubMed

    Ulaner, Gary A; D'Andrea, Gabriella; Cody, Hiram S

    2013-06-01

    A woman with bilateral breast cancer treated with bilateral mastectomies, implant reconstructions, chemotherapy, and hormonal therapy underwent FDG PET/CT imaging. Imaging demonstrated sternal, nodal, and lung lesions which were stable or slowly increasing, as well as a parasternal chest wall mass which was enlarging much more rapidly and was excised. Pathology of the chest wall mass demonstrated only benign soft tissue with fat necrosis and foreign body giant cell reaction, without evidence of malignancy or implant rupture. This case demonstrates how a benign FDG-avid foreign body reaction, induced by an intact breast prosthesis, could easily be mistaken for malignancy.

  15. Clinical applications of choline PET/CT in brain tumors.

    PubMed

    Giovannini, Elisabetta; Lazzeri, Patrizia; Milano, Amalia; Gaeta, Maria Chiara; Ciarmiello, Andrea

    2015-01-01

    Malignant gliomas and metastatic tumors are the most common forms of brain tumors. From a clinical perspective, neuroimaging plays a significant role, in diagnosis, treatment planning, and follow-up. To date MRI is considered the current clinical gold standard for imaging, however, despite providing superior structural detail it features poor specificity in identifying viable tumors in brain treated with surgery, radiation, or chemotherapy. In the last years functional neuroimaging has become largely widespread thanks to the use of molecular tracers employed in cellular metabolism which has significantly improved the management of patients with brain tumors, especially in the post-treatment phase. Despite the considerable progress of molecular imaging in oncology its use in the diagnosis of brain tumors is still limited by a few wellknown technical problems. Because 18F-FDG, the most common radiotracer used in oncology, is avidly accumulated by normal cortex, the low tumor/background signal ratio makes it difficult to distinguish the tumor from normal surrounding tissues. By contrast, radiotracers with higher specificity for the tumor are labeled with a short half-life isotopes which restricts their use to those centers equipped with a cyclotron and radiopharmacy facility. 11C-choline has been reported as a suitable tracer for neuroimaging application. The recent availability of choline labeled with a long half-life radioisotope as 18F increases the possibility of studying this tracer's potential role in the staging of brain tumors. The present review focuses on the possible clinical applications of PET/CT with choline tracers in malignant brain tumors and brain metastases, with a special focus on malignant gliomas.

  16. Radiation exposure to nuclear medicine staffs during 18F-FDG PET/CT procedures at Ramathibodi Hospital

    NASA Astrophysics Data System (ADS)

    Donmoon, T.; Chamroonrat, W.; Tuntawiroon, M.

    2016-03-01

    The aim of this study is to estimate the whole body and finger radiation doses per study received by nuclear medicine staff involved in dispensing, administration of 18F-FDG and interacting with radioactive patients during PET/CT imaging procedures in a PET/CT facility. The whole-body doses received by radiopharmacists, technologists and nurses were measured by electronic dosimeter and the finger doses by ring dosimeter during a period of 4 months. In 70 PET/CT studies, the mean whole-body dose per study to radiopharmacist, technologist, and nurse were 1.07±0.09, 1.77±0.46, μSv, and not detectable respectively. The mean finger doses per study received by radiopharmacist, technologist, and nurse were 265.65±107.55, 4.84±1.08 and 19.22±2.59 μSv, respectively. The average time in contact with 18F-FDG was 5.88±0.03, 39.06±1.89 and 1.21±0.02 minutes per study for radiopharmacist, technologist and nurse respectively. Technologists received highest mean effective whole- body dose per study and radiopharmacist received the highest finger dose per study. When compared with the ICRP dose limit, each individual worker can work with many more 18F- FDG PET/CT studies for a whole year without exceeding the occupational dose limits. This study confirmed that low levels of radiation does are received by our medical personnel involved in 18F-FDG PET/CT procedures.

  17. Comparison of FDG-PET/CT and CT for Delineation of Lumpectomy Cavity for Partial Breast Irradiation

    SciTech Connect

    Ford, Eric C. Lavely, William C.; Frassica, Deborah A.; Myers, Lee T.; Asrari, Fariba; Wahl, Richard L.; Zellars, Richard C.

    2008-06-01

    Purpose: The success of partial breast irradiation critically depends on proper target localization. We examined the use of fluorodeoxyglucose-positron emission tomography (FDG-PET)/computed tomography (CT) for improved lumpectomy cavity (LC) delineation and treatment planning. Methods and Materials: Twelve breast cancer patients underwent FDG-PET/CT on a GE Discovery scanner with a median time from surgery to PET/CT of 49 days. The LC was contoured on the CT scan by a radiation oncologist and, together with a nuclear medicine physician, on the PET/CT scan. The volumes were calculated and compared in each patient. Treatment planning target volumes (PTVs) were calculated by expanding the margin 2 cm beyond the LC, maintaining a 5-mm margin from the skin and chest wall, and the treatment plans were evaluated. In addition, a study with a patient-like phantom was conducted to evaluate the effect that the window/level settings might have on contouring. Results: The margin of the LC was well visualized on all FDG-PET images. The phantom results indicated that the difference between the known volume and the FDG-PET-delineated volume was <10%, regardless of the window/level settings. The PET/CT volumes were larger than the CT volumes in all cases (median volume ratio, 1.68; range, 1.24-2.45; p = 0.004). The PET/CT-based PTVs were also larger than the CT-based PTV (median volume ratio, 1.16; range, 1.08-1.64; p = 0.006). In 9 of 12 patients, a CT-based treatment plan did not provide adequate coverage of the PET/CT-based PTV (99% of the PTV received <95% of the prescribed dose), resulting in substantial cold spots in some plans. In these cases, treatment plans were generated which were specifically designed to cover the larger PET/CT-based PTV. Although these plans showed an increased dose to the normal tissues, the increases were modest: the non-target breast volume receiving {>=}50 Gy, lung volume receiving {>=}30 Gy, and heart volume receiving {>=}5 Gy increased by 5

  18. (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.

  19. The Role of 18F-Sodium Fluoride PET/CT Bone Scans in the Diagnosis of Metastatic Bone Disease from Breast and Prostate Cancer.

    PubMed

    Kulshrestha, Randeep Kumar; Vinjamuri, Sobhan; England, Andrew; Nightingale, Julie; Hogg, Peter

    2016-12-01

    We describe the role of (18)F-sodium fluoride ((18)F-NaF) PET/CT bone scanning in the staging of breast and prostate cancer. (18)F-NaF PET was initially utilized as a bone scanning agent in the 1960s and early 1970s, however, its use was restricted by the then-available γ-cameras. The advent of hybrid PET/CT cameras in the late 1990s has shown a resurgence of interest in its use and role. After a brief introduction, this paper describes the radiopharmaceutical properties, dosimetry, pharmacokinetics, and mechanism of uptake of (18)F-NaF. The performance of (18)F-NaF PET/CT is then compared with that of conventional bone scintigraphy using current evidence from the literature. Strengths and weaknesses of (18)F-NaF PET/CT imaging are highlighted. Clinical examples of improved accuracy of diagnosis and impact on patient management are illustrated. Limitations of (18)F-NaF PET/CT imaging are outlined.

  20. Low-Dose PET/CT and Full-Dose Contrast-Enhanced CT at the Initial Staging of Localized Diffuse Large B-Cell Lymphomas

    PubMed Central

    Sabaté-Llobera, Aida; Cortés-Romera, Montserrat; Mercadal, Santiago; Hernández-Gañán, Javier; Pomares, Helena; González-Barca, Eva; Gámez-Cenzano, Cristina

    2016-01-01

    Computed tomography (CT) has been used as the reference imaging technique for the initial staging of diffuse large B-cell lymphoma until recent days, when the introduction of positron emission tomography (PET)/CT imaging as a hybrid technique has become of routine use. However, the performance of both examinations is still common. The aim of this work was to compare the findings between low-dose 2-deoxy-2-(18F)fluoro-d-glucose (18F-FDG) PET/CT and full-dose contrast-enhanced CT (ceCT) in 28 patients with localized diffuse large B-cell lymphoma according to PET/CT findings, in order to avoid the performance of ceCT. For each technique, a comparison in the number of nodal and extranodal involved regions was performed. PET/CT showed more lesions than ceCT in both nodal (41 vs. 36) and extranodal localizations (16 vs. 15). Disease staging according to both techniques was concordant in 22 patients (79%) and discordant in 6 patients (21%), changing treatment management in 3 patients (11%). PET/CT determined a better staging and therapeutic approach, making the performance of an additional ceCT unnecessary. PMID:27559300

  1. Colorectal cancer and 18FDG-PET/CT: What about adding the T to the N parameter in loco-regional staging?

    PubMed Central

    Mainenti, Pier Paolo; Iodice, Delfina; Segreto, Sabrina; Storto, Giovanni; Magliulo, Mario; Palma, Giovanni Domenico De; Salvatore, Marco; Pace, Leonardo

    2011-01-01

    AIM: To evaluate whether FDG-positron emission tomography (PET)/computed tomography (CT) may be an accurate technique in the assessment of the T stage in patients with colorectal cancer. METHODS: Thirty four consecutive patients (20 men and 14 women; mean age: 63 years) with a histologically proven diagnosis of colorectal adenocarcinoma and scheduled for surgery in our hospital were enrolled in this study. All patients underwent FDG-PET/CT preoperatively. The primary tumor site and extent were evaluated on PET/CT images. Colorectal wall invasion was analysed according to a modified T classification that considers only three stages (≤ T2, T3, T4). Assessment of accuracy was carried out using 95% confidence intervals for T. RESULTS: Thirty five/37 (94.6%) adenocarcinomas were identified and correctly located on PET/CT images. PET/CT correctly staged the T of 33/35 lesions identified showing an accuracy of 94.3% (95% CI: 87%-100%). All T1, T3 and T4 lesions were correctly staged, while two T2 neoplasms were overstated as T3. CONCLUSION: Our data suggest that FDG-PET/CT may be an accurate modality for identifying primary tumor and defining its local extent in patients with colorectal cancer. PMID:21472100

  2. PET/CT for Radiotherapy Treatment Planning in Patients With Soft Tissue Sarcomas

    SciTech Connect

    Karam, Irene; Devic, Slobodan; Hickeson, Marc; Roberge, David; Turcotte, Robert E.; Freeman, Carolyn R.

    2009-11-01

    Purpose: To study the possibility of incorporating positron emission tomography/computed tomography (PET/CT) information into radiotherapy treatment planning in patients with high-grade soft tissue sarcomas (STS). Methods and Materials: We studied 17 patients treated with preoperative radiotherapy at our institution from 2005 to 2007. All patients had a high-grade STS and had had a staging PET/CT scan. For each patient, an MRI-based gross tumor volume (GTV), considered to be the contemporary standard for radiotherapy treatment planning, was outlined on a T1-gadolinium enhanced axial MRI (GTV{sub MRI}), and a second set of GTVs were outlined using different threshold values on PET images (GTV{sub PET}). PET-based target volumes were compared with the MRI-based GTV. Threshold values for target contouring were determined as a multiple (from 2 to 10 times) of the background soft tissue uptake values (B) sampled over healthy tissue. Results: PET-based GTVs contoured using a threshold value of 2 or 2.5 most closely resembled the GTV{sub MRI} volumes. Higher threshold values lead to PET volumes much smaller than the GTV{sub MRI}. The standard deviations between the average volumes of GTV{sub PET} and GTV{sub MRI} ratios for all thresholds were large, ranging from 36% for 2 xB up to 93% for 10 xB. Maximum uptake-to-background ratio correlated poorly with the maximum standardized uptake values. Conclusions: It is unlikely that PET/CT will make a significant contribution in GTV definition for radiotherapy treatment planning in patients with STS using threshold methods on PET images. Future studies will focus on molecular imaging and tumor physiology.

  3. Breast Fibroadenoma With Increased Activity on 68Ga DOTATATE PET/CT.

    PubMed

    Papadakis, Georgios Z; Millo, Corina; Sadowski, Samira M; Karantanas, Apostolos H; Bagci, Ulas; Patronas, Nicholas J

    2017-02-01

    Fibroadenoma is the most common benign breast tumor in women of reproductive age, carrying little to no risk of breast cancer development. We report on a case of a woman with history of neuroendocrine tumor who on follow-up imaging tests underwent whole-body PET/CT study using Ga DOTATATE. The scan showed increased focal activity in the right breast, which was biopsied revealing a fibroadenoma. The presented data suggests cell surface overexpression of somatostatin receptors by this benign breast tumor. Moreover, this finding emphasizes the need for cautious interpretation of Ga DOTATATE-avid breast lesions that could mimic malignancy in neuroendocrine tumor patients.

  4. Endolymphatic Sac Tumor Showing Increased Activity on 68Ga DOTATATE PET/CT.

    PubMed

    Papadakis, Georgios Z; Millo, Corina; Sadowski, Samira M; Bagci, Ulas; Patronas, Nicholas J

    2016-10-01

    Endolymphatic sac tumors (ELSTs) are rare tumors arising from the epithelium of the endolymphatic sac and duct that can be either sporadic or associated with von Hippel-Lindau (VHL) disease. We report a case of a VHL patient with histologically proven residual ELST who underwent Ga DOTATATE PET/CT showing increased activity (SUVmax, 6.29) by the ELST. The presented case of a VHL-associated ELST with increased Ga DOTATATE uptake indicates cell-surface expression of somatostatin receptors by this tumor, suggesting the potential application of somatostatin receptor imaging using Ga DOTA-conjugated peptides in the workup and management of these patients.

  5. PET CT Identifies Reactivation Risk in Cynomolgus Macaques with Latent M. tuberculosis

    PubMed Central

    Lin, Philana Ling; Maiello, Pauline; Gideon, Hannah P.; Cadena, Anthony M.; Rodgers, Mark A.; Gregg, Robert; O’Malley, Melanie; Fillmore, Daniel; Frye, L. James; Rutledge, Tara; DiFazio, Robert M.; Janssen, Christopher; Klein, Edwin; Andersen, Peter L.; Fortune, Sarah M.; Flynn, JoAnne L.

    2016-01-01

    Mycobacterium tuberculosis infection presents across a spectrum in humans, from latent infection to active tuberculosis. Among those with latent tuberculosis, it is now recognized that there is also a spectrum of infection and this likely contributes to the variable risk of reactivation tuberculosis. Here, functional imaging with 18F-fluorodeoxygluose positron emission tomography and computed tomography (PET CT) of cynomolgus macaques with latent M. tuberculosis infection was used to characterize the features of reactivation after tumor necrosis factor (TNF) neutralization and determine which imaging characteristics before TNF neutralization distinguish reactivation risk. PET CT was performed on latently infected macaques (n = 26) before and during the course of TNF neutralization and a separate set of latently infected controls (n = 25). Reactivation occurred in 50% of the latently infected animals receiving TNF neutralizing antibody defined as development of at least one new granuloma in adjacent or distant locations including extrapulmonary sites. Increased lung inflammation measured by PET and the presence of extrapulmonary involvement before TNF neutralization predicted reactivation with 92% sensitivity and specificity. To define the biologic features associated with risk of reactivation, we used these PET CT parameters to identify latently infected animals at high risk for reactivation. High risk animals had higher cumulative lung bacterial burden and higher maximum lesional bacterial burdens, and more T cells producing IL-2, IL-10 and IL-17 in lung granulomas as compared to low risk macaques. In total, these data support that risk of reactivation is associated with lung inflammation and higher bacterial burden in macaques with latent Mtb infection. PMID:27379816

  6. MicroPET/CT Colonoscopy in long-lived Min mouse using NM404

    NASA Astrophysics Data System (ADS)

    Christensen, Matthew B.; Halberg, Richard B.; Schutten, Melissa M.; Weichert, Jamey P.

    2009-02-01

    Colon cancer is a leading cause of death in the US, even though many cases are preventable if tumors are detected early. One technique to promote screening is Computed Tomography Colonography (CTC). NM404 is a second generation phospholipid ether analogue which has demonstrated selective uptake and prolonged retention in 43/43 types of malignant tumors but not inflammatory sites or premalignant lesions. The purpose of this experiment was to evaluate (SWR x B6 )F1.Min mice as a preclinical model to test MicroPET/CT dual modality virtual colonoscopy. Each animal was given an IV injection of 124I-NM404 (100 uCi) 24, 48 and 96 hours prior to scanning on a dedicated microPET/CT system. Forty million counts were histogrammed in 3D and reconstructed using an OSEM 2D algorithm. Immediately after PET acquisition, a 93 m volumetric CT was acquired at 80 kVp, 800 uA and 350 ms exposures. Following CT, the mouse was sacrificed. The entire intestinal tract was excised, washed, insufflated, and scanned ex vivo A total of eight tissue samples from the small intestine were harvested: 5 were benign adenomas, 2 were malignant adenocarcinomas, and 1 was a Peyer's patch (lymph tissue) . The sites of these samples were positioned on CT and PET images based on morphological cues and the distance from the anus. Only 1/8 samples showed tracer uptake. several hot spots in the microPET image were not chosen for histology. (SWR x B6)F1.Min mice develop benign and malignant tumors, making this animal model a strong candidate for future dual modality microPET/CT virtual colonography studies.

  7. Value of 18F-FDG PET and PET/CT for evaluation of pediatric malignancies.

    PubMed

    Uslu, Lebriz; Donig, Jessica; Link, Michael; Rosenberg, Jarrett; Quon, Andrew; Daldrup-Link, Heike E

    2015-02-01

    Successful management of solid tumors in children requires imaging tests for accurate disease detection, characterization, and treatment monitoring. Technologic developments aim toward the creation of integrated imaging approaches that provide a comprehensive diagnosis with a single visit. These integrated diagnostic tests not only are convenient for young patients but also save direct and indirect health-care costs by streamlining procedures, minimizing hospitalizations, and minimizing lost school or work time for children and their parents. (18)F-FDG PET/CT is a highly sensitive and specific imaging modality for whole-body evaluation of pediatric malignancies. However, recent concerns about ionizing radiation exposure have led to a search for alternative imaging methods, such as whole-body MR imaging and PET/MR. As we develop new approaches for tumor staging, it is important to understand current benchmarks. This review article will synthesize the current literature on (18)F-FDG PET/CT for tumor staging in children, summarizing questions that have been solved and providing an outlook on unsolved avenues.

  8. Polysplenia Syndrome With Splenic and Skeletal Muscle Metastases From Thyroid Carcinoma Evaluated by FDG PET/CT: Case Report and Literature Review

    PubMed Central

    Li, Zu-Gui; Lin, Zhi-Chun; Mu, Hai-Yu

    2016-01-01

    Abstract Polysplenia syndrome (PSS) is a rare congenital abnormality. Metastases to spleen and skeletal muscle from differentiated thyroid cancer (DTC) are also extremely rare. Our case report aims to present an interesting case of PSS associated with splenic metastasis (SM) and skeletal muscle metastasis (SMM) from advanced papillary thyroid carcinoma which was evaluated on fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT). An 84-year-old Chinese man was admitted with the history of multiple enlarged masses in bilateral neck, right axillary, and inguinal areas for >2 months. The results of ultrasonography examination were highly suggestive of malignancy. The histological results of the following biopsy were consistent with papillary thyroid carcinoma with involvement of multiple regional lymph nodes. He was referred for an FDG PET/CT imaging to evaluate the situation. FDG PET/CT showed that an intense FDG-avid thyroid mass with widespread regional lymph node involvement and distant metastases in the body. Unexpected sites of metastases were detected in the spleens and skeletal muscles. Most interestingly, FDG PET/CT imaging also described the typical imaging findings of PSS including the 2 right-sided spleens, azygos and hemiazygos continuation of inferior vena cava (IVC), right-sided stomach, middle line liver, a short pancreas, preduodenal portal vein (PPV), and malrotation of gut. Whole body FDG PET/CT imaging can accurately evaluate the situation of DTC by detecting regional lymph node involvement, common and rare sites of distant metastases which are closely related to staging, management, and prognosis of this disease. Whole-body FDG PET/CT is also valuable in demonstrating the typical imaging features of PSS. PMID:26825891

  9. Polysplenia Syndrome With Splenic and Skeletal Muscle Metastases From Thyroid Carcinoma Evaluated by FDG PET/CT: Case Report and Literature Review: A Care-Compliant Article.

    PubMed

    Li, Zu-Gui; Lin, Zhi-Chun; Mu, Hai-Yu

    2016-01-01

    Polysplenia syndrome (PSS) is a rare congenital abnormality. Metastases to spleen and skeletal muscle from differentiated thyroid cancer (DTC) are also extremely rare. Our case report aims to present an interesting case of PSS associated with splenic metastasis (SM) and skeletal muscle metastasis (SMM) from advanced papillary thyroid carcinoma which was evaluated on fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT). An 84-year-old Chinese man was admitted with the history of multiple enlarged masses in bilateral neck, right axillary, and inguinal areas for >2 months. The results of ultrasonography examination were highly suggestive of malignancy. The histological results of the following biopsy were consistent with papillary thyroid carcinoma with involvement of multiple regional lymph nodes. He was referred for an FDG PET/CT imaging to evaluate the situation. FDG PET/CT showed that an intense FDG-avid thyroid mass with widespread regional lymph node involvement and distant metastases in the body. Unexpected sites of metastases were detected in the spleens and skeletal muscles. Most interestingly, FDG PET/CT imaging also described the typical imaging findings of PSS including the 2 right-sided spleens, azygos and hemiazygos continuation of inferior vena cava (IVC), right-sided stomach, middle line liver, a short pancreas, preduodenal portal vein (PPV), and malrotation of gut. Whole body FDG PET/CT imaging can accurately evaluate the situation of DTC by detecting regional lymph node involvement, common and rare sites of distant metastases which are closely related to staging, management, and prognosis of this disease. Whole-body FDG PET/CT is also valuable in demonstrating the typical imaging features of PSS.

  10. (18)F-FDG PET/CT quantification in head and neck squamous cell cancer: principles, technical issues and clinical applications.

    PubMed

    Manca, Gianpiero; Vanzi, Eleonora; Rubello, Domenico; Giammarile, Francesco; Grassetto, Gaia; Wong, Ka Kit; Perkins, Alan C; Colletti, Patrick M; Volterrani, Duccio

    2016-07-01

    (18)F-FDG PET/CT plays a crucial role in the diagnosis and management of patients with head and neck squamous cell cancer (HNSCC). The major clinical applications of this method include diagnosing an unknown primary tumour, identifying regional lymph node involvement and distant metastases, and providing prognostic information. (18)F-FDG PET/CT is also used for precise delineation of the tumour volume for radiation therapy planning and dose painting, and for treatment response monitoring, by detecting residual or recurrent disease. Most of these applications would benefit from a quantitative approach to the disease, but the quantitative capability of (18)F-FDG PET/CT is still underused in HNSCC. Innovations in PET/CT technology promise to overcome the issues that until now have hindered the employment of dynamic procedures in clinical practice and have limited "quantification" to the evaluation of standardized uptake values (SUV), de facto a semiquantitative parameter, the limits of which are well known to the nuclear medicine community. In this paper the principles of quantitative imaging and the related technical issues are reviewed so that professionals involved in HNSCC management can reflect on the advantages of "true" quantification. A discussion is then presented on how semiquantitative information is currently used in clinical (18)F-FDG PET/CT applications in HNSCC, by discussing the improvements that could be obtained with more advanced and "personalized" quantification techniques.

  11. FDG PET/CT of extranodal involvement in non-Hodgkin lymphoma and Hodgkin disease.

    PubMed

    Paes, Fabio M; Kalkanis, Dimitrios G; Sideras, Panagiotis A; Serafini, Aldo N

    2010-01-01

    The term extranodal disease refers to lymphomatous infiltration of anatomic sites other than the lymph nodes. Almost any organ can be affected by lymphoma, with the most common extranodal sites of involvement being the stomach, spleen, Waldeyer ring, central nervous system, lung, bone, and skin. The prevalence of extranodal involvement in non-Hodgkin lymphoma and Hodgkin disease has increased in the past decade. The imaging characteristics of extranodal involvement can be subtle or absent at conventional computed tomography (CT). Imaging of tumor metabolism with 2-[fluorine-18]fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (PET) has facilitated the identification of affected extranodal sites, even when CT has demonstrated no lesions. More recently, hybrid PET/CT has become the standard imaging modality for initial staging, follow-up, and treatment response assessment in patients with lymphoma and has proved superior to CT in these settings. Certain PET/CT patterns are suggestive of extranodal disease and can help differentiate tumor from normal physiologic FDG activity, particularly in the mucosal tissues, bone marrow, and organs of the gastrointestinal tract. Familiarity with the different extranodal manifestations in various locations is critical for correct image interpretation. In addition, a knowledge of the differences in FDG avidity among the histologic subtypes of lymphoma, appropriate timing of scanning after therapeutic interventions, and use of techniques to prevent brown fat uptake are essential for providing the oncologist with accurate information.

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

    SciTech Connect

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

    2015-06-15

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

  13. A New Method of Detecting Pulmonary Nodules with PET/CT Based on an Improved Watershed Algorithm

    PubMed Central

    Zhao, Juanjuan; Ji, Guohua; Qiang, Yan; Han, Xiaohong; Pei, Bo; Shi, Zhenghao

    2015-01-01

    Background Integrated 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) is widely performed for staging solitary pulmonary nodules (SPNs). However, the diagnostic efficacy of SPNs based on PET/CT is not optimal. Here, we propose a method of detection based on PET/CT that can differentiate malignant and benign SPNs with few false-positives. Method Our proposed method combines the features of positron-emission tomography (PET) and computed tomography (CT). A dynamic threshold segmentation method was used to identify lung parenchyma in CT images and suspicious areas in PET images. Then, an improved watershed method was used to mark suspicious areas on the CT image. Next, the support vector machine (SVM) method was used to classify SPNs based on textural features of CT images and metabolic features of PET images to validate the proposed method. Results Our proposed method was more efficient than traditional methods and methods based on the CT or PET features alone (sensitivity 95.6%; average of 2.9 false positives per scan). PMID:25853496

  14. Radiation dose to radiosensitive organs in PET/CT myocardial perfusion examination using versatile optical fibre

    NASA Astrophysics Data System (ADS)

    Salasiah, M.; Nordin, A. J.; Fathinul Fikri, A. S.; Hishar, H.; Tamchek, N.; Taiman, K.; Ahmad Bazli, A. K.; Abdul-Rashid, H. A.; Mahdiraji, G. A.; Mizanur, R.; Noor, Noramaliza M.

    2013-05-01

    Cardiac positron emission tomography (PET) provides a precise method in order to diagnose obstructive coronary artery disease (CAD), compared to single photon emission tomography (SPECT). PET is suitable for obese and patients who underwent pharmacologic stress procedures. It has the ability to evaluate multivessel coronary artery disease by recording changes in left ventricular function from rest to peak stress and quantifying myocardial perfusion (in mL/min/g of tissue). However, the radiation dose to the radiosensitive organs has become crucial issues in the Positron Emission Tomography/Computed Tomography(PET/CT) scanning procedure. The objective of this study was to estimate radiation dose to radiosensitive organs of patients who underwent PET/CT myocardial perfusion examination at Centre for Diagnostic Nuclear Imaging, Universiti Putra Malaysia in one month period using versatile optical fibres (Ge-B-doped Flat Fibre) and LiF (TLD-100 chips). All stress and rest paired myocardial perfusion PET/CT scans will be performed with the use of Rubidium-82 (82Rb). The optic fibres were loaded into plastic capsules and attached to patient's eyes, thyroid and breasts prior to the infusion of 82Rb, to accommodate the ten cases for the rest and stress PET scans. The results were compared with established thermoluminescence material, TLD-100 chips. The result shows that radiation dose given by TLD-100 and Germanium-Boron-doped Flat Fiber (Ge-B-doped Flat Fiber) for these five organs were comparable to each other where the p>0.05. For CT scans,thyroid received the highest dose compared to other organs. Meanwhile, for PET scans, breasts received the highest dose.

  15. Use of subsequent PET/CT in diffuse large B-cell lymphoma patients in complete remission following primary therapy.

    PubMed

    Zhang, Xu; Fan, Wei; Xia, Zhong-Jun; Hu, Ying-Ying; Lin, Xiao-Ping; Zhang, Ya-Rui; Li, Zhi-Ming; Liang, Pei-Yan; Li, Yuan-Hua

    2015-02-01

    Interim 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (I-PET/CT) is a powerful tool for monitoring the response to therapy in diffuse large B-cell lymphoma (DLBCL). This retrospective study aimed to determine when and how to use I-PET/CT in DLBCL. A total of 197 patients treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) were enrolled between October 2005 and July 2011; PET/CT was performed at the time of diagnosis (PET/CT0), after 2 and 4 cycles of chemotherapy (PET/CT2 and PET/CT4, respectively), and at the end of treatment (F-PET/CT). According to the International Harmonization Project for Response Criteria in Lymphoma, 110 patients had negative PET/CT2 scans, and 87 had positive PET/CT2 scans. The PET/CT2-negative patients had significantly higher 3-year progression-free survival rate (75.8% vs. 38.2%) and 3-year overall survival rate (93.5% vs. 55.6%) than PET/CT2-positive patients. All PET/CT2-negative patients remained negative at PET/CT4, but 3 were positive at F-PET/CT. Among the 87 PET/CT2-positive patients, 57 remained positive at F-PET/CT, and 32 progressed during chemotherapy (15 at PET/CT4 and 17 at F-PET/CT). Comparing PET/CT4 with PET/CT0, 7 patients exhibited progression, and 8 achieved partial remission. Comparing F-PET/CT with PET/CT0, 10 patients exhibited progression, and 7 achieved partial remission. In conclusion, our results indicate that I-PET/CT should be performed after 2 rather than 4 cycles of immunochemotherapy in DLBCL patients. There is a limited role for subsequent PET/CT in the detection of relapse in PET/CT2-negative patients, but repeat PET/CT is required if the PET/CT2 findings are positive.

  16. Fluorine-18 fluorodeoxyglucose PET/CT patterns of extranodal involvement in patients with Non-Hodgkin lymphoma and Hodgkin's disease.

    PubMed

    Even-Sapir, Einat; Lievshitz, Genady; Perry, Chava; Herishanu, Yair; Lerman, Hedva; Metser, Ur

    2007-07-01

    Lymphoma may originate in extranodal sites. Extranodal lymphoma may also be secondary to and accompany nodal disease. Fluorine-18 fluorodeoxyglucose (18F-FDG) imaging has an essential role in the staging of lymphoma, in monitoring the response to therapy, and in detection of recurrence. The introduction of 18F-FDG PET/CT hybrid imaging allows for accurate localization of disease and may be specifically beneficial for the detection of unexpected extranodal sites of disease or exclusion of disease in the presence of nonspecific extranodal CT findings. Accurate staging and localization often dictate the appropriate treatment strategy in patients with lymphoma. Therefore, at any stage in the course of the disease, the potential presence of extranodal disease should be considered when interpreting 18F-FDG PET/CT studies in patients with non-Hodgkin lymphoma and Hodgkin's disease.

  17. Variability of Gross Tumor Volume Delineation in Head-and-Neck Cancer Using PET/CT Fusion, Part II: The Impact of a Contouring Protocol

    SciTech Connect

    Berson, Anthony M. Stein, Nicholas F.; Riegel, Adam C.; Destian, Sylvie; Ng, Tracy; Tena, Lawrence B.; Mitnick, Robin J.; Heiba, Sherif

    2009-04-01

    The purpose of this study was to assess the efficacy of a gross tumor volume (GTV) contouring protocol on interobserver variability between 4 physicians in positron emission therapy/computed tomography (PET/CT) treatment planning of head-and-neck cancer. A GTV contouring protocol for PET/CT treatment planning was developed utilizing 4 stages: Preliminary contouring on CT alone, determination of appropriate PET windowing, accurate image registration, and modification of CT contouring with correctly formatted PET/CT display and rules for modality disagreement. Two neuroradiologists and 2 radiation oncologists (designated as A, B, C, and D, respectively) were given a tutorial of PET/CT coregistered imaging individualized to their skill level, which included a step-by-step explanation of the protocol with clinical examples. Opportunities for questions and hands-on practice were given. The physicians were asked to re-contour 16 head-and-neck patients from Part I on PET/CT fusion imaging. Differences in volume magnitude were analyzed for statistical significance by analysis of variance (ANOVA) and paired t-tests ({alpha} < 0.05). Volume overlap was analyzed for statistical significance using Wilcoxon signed-rank tests ({alpha} < 0.05). Volume overlap increased significantly from Part I to Part II (p < 0.05). One previously significant difference between physicians disappeared with the protocol in place. The mean fusion volume of Physician C, however, remained significantly larger than that of Physician D (p < 0.01). This result is unchanged from Part I. The multidisciplinary contouring protocol significantly improved the coincidence of GTVs contoured by multiple physicians. The magnitudes of the volumes showed marginal improvement in consistency. Developing an institutional contouring protocol for PET/CT treatment planning is highly recommended to reduce interobserver variability.

  18. Systemic Immune Response to Vaccination on FDG-PET/CT.

    PubMed

    Mingos, Mark; Howard, Stephanie; Giacalone, Nicholas; Kozono, David; Jacene, Heather

    2016-12-01

    A patient with newly diagnosed right lung cancer had transient (18)F-fluorodeoxyglucose (FDG)-avid left axillary lymph nodes and intense splenic FDG uptake on positron emission tomography (PET)/computed tomography (CT). History revealed that the patient received a left-sided influenza vaccine 2-3 days before the examination. Although inflammatory FDG uptake in ipsilateral axillary nodes is reported, to our knowledge, this is the first report of visualization of the systemic immune response in the spleen related to the influenza vaccination on FDG-PET/CT. The history, splenic uptake and time course on serial FDG-PET/CT helped to avoid a false-positive interpretation for progressing lung cancer and alteration of the radiation therapy plan.

  19. Case report of primary renal pelvis squamous cell carcinoma coexisting with long-standing calculi in left kidney on 18F-FDG PET/CT

    PubMed Central

    Deng, Shengming; Zhang, Bin; Huang, Ying; Li, Jihui; Sang, Shibiao; Zhang, Wei

    2017-01-01

    Abstract Rationale: Primary renal pelvis squamous cell carcinoma (SCC) is an extremely rare neoplasm. In many patients, the SCC was associated with renal calculi. Patient concerns: A 61-year-old male presented with intermittent pain at the left lumbar region for 3 days. The PET/CT images demonstrated increased 18F-FDG uptake in the upper pole of the left kidney and left renal hilar lymph nodes. Diagnoses: Pathologic examination revealed well-moderately differentiated renal pelvis SCC with lymphatic metastasis. Interventions: The patient underwent a left nephrectomy a few days after the initial staging PET/CT study. Outcomes: No growing lesion or metastasis was observed during a 6-month follow-up. Lessons: Our case demonstrates that 18F-FDG PET/CT is a useful diagnostic tool to evaluate primary renal pelvic SCC and detect metastatic lymph nodes in patients with long-standing calculi. PMID:28296764

  20. (18)F-DOPA PET/CT for assessment of response to induction chemotherapy in a child with high-risk neuroblastoma.

    PubMed

    Piccardo, Arnoldo; Lopci, Egesta; Foppiani, Luca; Morana, Giovanni; Conte, Massimo

    2014-03-01

    Functional imaging plays a crucial role in the assessment of neuroblastoma. The evaluation of response to induction chemotherapy is a cornerstone in scheduling proper treatment management in patients affected by high-risk neuroblastoma. (123)I-metaiodobenzylguanidine has been recognized as the radiopharmaceutical of choice in neuroblastoma assessment. To date, the clinical role of PET/CT in pediatric malignancy is not well established.(18)F-DOPA-PET/CT has been recently used in neuroblastoma, and compared with (123)I-MIBG-scan. Scant new data are available about the role of this tool in the evaluation of treatment response after induction chemotherapy. We investigate the role of (18)F-DOPA-PET/CT in characterizing the response to induction chemotherapy in a child affected by high-risk-neuroblastoma, in whom the rare association of (123)I-MIBG-negative primary tumor and MIBG-positive bone marrow metastases was observed.

  1. [18F-FDG PET/CT diagnosis of liver cyst infection in a patient with autosomal dominant polycystic kidney disease and fever of unknown origin].

    PubMed

    Banzo, J; Ubieto, M A; Gil, D; Prats, E; Razola, P; Tardín, L; Andrés, A; Rambalde, E F; Ayala, S M; Cáncer, L; Velilla, J

    2013-01-01

    The diagnosis, localization and treatment of infected cysts in the kidney or liver of patients with autosomal dominant polycystic kidney disease (ADPKD) remain a clinical challenge. We report the findings of (18)F-FDG PET-CT in an ADPKD diagnosed patient who required renal transplantation five years before and in his follow up presented repeated episodes of bacteriemia without known focus on radiological tests performed. The (18)F-FDG PET-CT scan showed numerous hypermetabolic images with focal or ring-shaped morphology related to the content and the wall of some hepatic cysts. The increased metabolic activity was localized on segments VI and VII. We proceeded to drainage of one cyst in segment VI, removing 110 cc of purulent fluid which grew E. Coli BLEE. The (18)F-FDG PET/CT scan should be included in the diagnostic algorithm for detecting infected liver cysts in patients with ADPKD and fever of unknown origin.

  2. Utility of [18F] Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (FDG PET/CT) in the Initial Staging and Response Assessment of Locally Advanced Breast Cancer Patients Receiving Neoadjuvant Chemotherapy.

    PubMed

    Hulikal, Narendra; Gajjala, Sivanath Reddy; Kalawat, Teck Chand; Kottu, Radhika; Amancharla Yadagiri, Lakshmi

    2015-12-01

    In India up to 50 % of breast cancer patients still present as locally advanced breast cancer (LABC). The conventional methods of metastatic work up include physical examination, bone scan, chest & abdominal imaging, and biochemical tests. It is likely that the conventional staging underestimates the extent of initial spread and there is a need for more sophisticated staging procedure. The PET/CT can detect extra-axillary and occult distant metastases and also aid in predicting response to chemotherapy at an early point in time. To evaluate the utility of FDG PET/CT in initial staging and response assessment of patients with LABC receiving NACT. A prospective study of all biopsy confirmed female patients diagnosed with LABC receiving NACT from April 2013 to May 2014. The conventional work up included serum chemistry, CECT chest and abdomen and bone scan. A baseline whole body PET/CT was done in all patients. A repeat staging evaluation and a whole body PET/CT was done after 2/3rd cycle of NACT in non-responders and after 3/4 cycles in clinical responders. The histopathology report of the operative specimen was used to document the pathological response. The FDG PET/CT reported distant metastases in 11 of 38 patients, where as conventional imaging revealed metastases in only 6. Almost all the distant lesions detected by conventional imaging were detected with PET/CT, which showed additional sites of metastasis in 3 patients. In 2 patients, PET/CT detected osteolytic bone metastasis which were not detected by bone scan. In 5 patients PET CT detected N3 disease which were missed on conventional imaging. A total of 14 patients had second PET/CT done to assess the response to NACT and 11 patients underwent surgery. Two patients had complete pathological response. Of these 1 patient had complete metabolic and morphologic response and other had complete metabolic and partial morphologic response on second PET/CT scan. The 18 FDG PET/CT can detect more number of

  3. Purulent lupus panniculitis unmasked by FDG-PET/CT scan

    PubMed Central

    van der Geest, Kornelis S.M.; Moerman, Rada V.; Koopmans, Klaas P.; Holman, Nicole D.; Janssen, Wilbert M.T.

    2016-01-01

    Abstract Rationale: Lupus panniculitis (LP) is a unique variant of cutaneous lupus erythematosus. Clinical manifestations are typically mild and include erythema, nodules, and small ulcers. In certain cases, diagnosing LP may be challenging. Skin overlying the typical subcutaneous inflammation may appear normal, and bacterial superinfections of the skin sometimes mask the underlying LP. It has been suggested that a computed tomography (CT) scan may help to identify obscure LP lesions. Here, we report a case of a 54-year-old woman with an unusually severe form of LP, in which the full disease extent was only revealed by a fluorodeoxyglucose positron emission tomography (FDG-PET)/CT scan. Patient concerns/Diagnoses/Interventions/Outcomes: Our patient initially presented with a bacterial infection of the skin. After initial improvement with antibiotic treatment, new erythematous lesions and sterile subcutaneous pus collections developed. An FDG-PET/CT scan revealed extensive subcutaneous inflammation at sites that had appeared normal during physical examination and on CT scan. As the subcutaneous lesions showed a remarkably linear pattern on FDG-PET/CT scan, the patient was suspected of having LP. After confirmation of this diagnosis by a deep-skin biopsy, our patient was treated with systemic glucocorticoids. Eventually, our patient succumbed to complications of LP and its treatment. Lessons: Our case demonstrates that clinical manifestations of LP are not always mild and that timely diagnosis is needed. Furthermore, we show that obscure LP lesions are more readily identified on an FDG-PET/CT scan than CT scan. PMID:27902603

  4. Dosimetric evaluation of the staff working in a PET/CT department

    NASA Astrophysics Data System (ADS)

    Dalianis, K.; Malamitsi, J.; Gogou, L.; Pagou, M.; Efthimiadou, R.; Andreou, J.; Louizï, A.; Georgiou, E.

    2006-12-01

    The dosimetric literature data concerning the medical personnel working in positron emission tomography/computed tomography (PET/CT) departments are limited. Therefore, we measured the radiation dose of the staff working in the first PET/CT department in Greece at the Diagnostic and Therapeutic Center of Athens HYGEIA—Harvard Medical International. As, for the time being, only 2-deoxy-2-[ 18F]fluoro-d-glucose (FDG) PET studies are performed, radiation dose measurements concern those derived from dispensing of the radiopharmaceutical as well as from the patients undergoing FDG-PET imaging. Our aim is to develop more effective protective measures against radionuclide exposure. To estimate the effective dose from external exposure, all seven members of the staff (two nurses, two medical physicists, two technologists, one secretary) had TLD badges worn at the upper pocket of their overall, TLD rings on the right hand and digital dosimeters at their upper side pocket. In addition, isodose curves were measured with thermoluminescence detectors for distances of 20, 50, 70 and 100 cm away from patients who had been injected with 18F-FDG. Dose values of the PET/CT staff were measured with digital detectors, TLD badges and TLD rings over the first 8 months for a total of 160 working days of the department's operation, consisting of a workload of about 10-15 patients/week who received 250-420 MBq of 18F-FDG each. Whole - body collective doses and hand doses for the staff were the following: Nurse #1 received 1.6 mSv as a whole body dose and 2,1 as a hand dose, Nurse #2 received 1.9 and 2.4 mSv respectively. For medical physicist #1 the dose values were 1.45 mSv whole body and 1.7 mSv hand dose, for medical physicist #2 1.67 mSv wholebody dose and 1.55 mSv hand dose and for technologists #1 & #2 the whole body doses were 0.7 and 0.64 mSv respectively. Lastly, the secretary received 0.1 mSv whole body dose. These preliminary data have shown that the dose levels of our PET/CT

  5. [Findings of the (18)F-FDG PET-CT in a cardiac angiosarcoma complicated by a cardiac rupture].

    PubMed

    Santiago-Chinchilla, Alicia; Ruiz-Carazo, Eduardo; Moral-Ruiz, Antonio; Testart Dardel, Nathalie; Martínez-Martínez, Alberto; López-Fernández, Silvia

    2014-01-01

    Primary malignant tumors of the heart are a rare condition. The most common type is the cardiac angiosarcoma. The symptoms of this disease are very nonspecific and can be very difficult to diagnose by conventional imaging techniques. We report the case of a male patient with cardiac angiosarcoma who also had a rare complication, this being cardiac rupture, which required the use of (18)F-FDG PET-CT to demonstrate the mass malignancy and to reach a definitive diagnosis.

  6. FDG PET/CT in Early and Late Stages of SAPHO Syndrome: Two Case Reports With MRI and Bone Scintigraphy Correlation.

    PubMed

    Dong, Aisheng; Bai, Yushu; Cui, Yong; Zhang, Jian; Zuo, Changjing

    2016-04-01

    Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome is a rare disease, which may be underdiagnosed or misdiagnosed because of nonspecific clinical and imaging findings. We present 2 cases of SAPHO syndrome with MRI, bone scintigraphy, and FDG PET/CT findings. In case 1 with early-stage disease, the active osteitis showed osteolytic bone destruction with increased FDG uptake. In case 2 with late-stage disease, the inactive bone lesions presented as osteosclerosis with normal FDG uptake. Familiarity with the FDG PET/CT findings of SAPHO syndrome in different stages may be helpful for correct diagnosis.

  7. Repeatability of quantitative FDG-PET/CT and contrast enhanced CT in recurrent ovarian carcinoma: test retest measurements for tumor FDG uptake, diameter and volume

    PubMed Central

    Rockall, Andrea G.; Avril, Norbert; Lam, Raymond; Iannone, Robert; Mozley, P. David; Parkinson, Christine; Bergstrom, Donald; Sala, Evis; Sarker, Shah-Jalal; McNeish, Iain A.; Brenton, James D.

    2014-01-01

    Purpose Repeatability of baseline FDG-PET/CT measurements has not been tested in ovarian cancer. This dual-center, prospective study assessed variation in tumor FDG uptake, tumor diameter (TD) and tumor volume (TV) from sequential FDG-PET/CT and contrast-enhanced CT (CECT) in patients with recurrent platinum-sensitive ovarian cancer. Methods Patients underwent two pre-treatment baseline FDG-PET/CT (n=21) and CECT (n=20) at 2 clinical sites with different PET/CT instruments. Patients were included if they had at least one target lesion (TL) in the abdomen with an SUV maximum (SUVmax) of ≥2.5 and a long axis diameter of ≥15mm. Two independent reading methods were used to evaluate repeatability of TD and SUV uptake: on site and at an imaging clinical research organization (CRO). TV reads were only performed by CRO. In each reading set, TLs were independently measured on sequential imaging. Results Median time between FDG-PET/CT was 2 days (range 1-7). For site reads, concordance correlation coefficient (CCC) for SUVmean, SUVmax and TD were 0.95, 0.94 and 0.99 respectively. Repeatability coefficients were 16.3%, 17.3% and 8.8% for SUVmean, SUVmax and TD respectively. Similar results were observed for CRO reads. TV CCC was 0.99 with a repeatability coefficient of 28.1%. Conclusions There was excellent test/retest repeatability for FDG-PET/CT quantitative measurements across two sites and two independent reading methods. Cut-off values for determining change in SUVmean, SUVmax and TV establish limits to determine metabolic and/or volumetric response to treatment in platinum-sensitive relapsed ovarian cancer. PMID:24573555

  8. Metabolic characteristics distinguishing intrahepatic cholangiocarcinoma: a negative pilot study of 18F-fluorocholine PET/CT clarified by transcriptomic analysis

    PubMed Central

    Kwee, Sandi A; Okimoto, Gordon S; Chan, Owen TM; Tiirikainen, Maarit; Wong, Linda L

    2016-01-01

    PET using fluorine-18 fluorocholine (18F-fluorocholine) may detect malignancies that involve altered choline metabolism. While 18F-fluorocholine PET/CT has shown greater sensitivity for detecting hepatocellular carcinoma (HCC) than 18F-fluoro-D-deoxyglucose (FDG) PET/CT, it is not known whether it can also detect intrahepatic cholangiocarcinoma (ICC), a less common form of primary liver cancer. Clinical, radiographic, and histopathologic data from 5 patients with ICC and 23 patients with HCC from a diagnostic trial of liver 18F-fluorocholine PET/CT imaging were analyzed to preliminarily evaluate 18F-fluorocholine PET/CT for ICC. Imaging was correlated with whole-genome expression profiling to identify molecular pathways associated with tumor phenotypes. On PET/CT, all ICC tumors demonstrated low 18F-fluorocholine uptake with a significantly lower tumor to mean background uptake ratio than HCC tumors (0.69 vs. 1.64, p < 0.0001), but no corresponding significant difference in liver parenchyma uptake of 18F-fluorocholine between ICC and HCC patients (8.0 vs. 7.7, p = 0.74). Two ICC patients demonstrated increased tumor metabolism on FDG PET/CT, while immunohistochemical analysis of ICC tumors revealed overexpression of glucose transporter 1 (GLUT-1) and hexokinase indicating a hyper-glycolytic phenotype. Gene expression analysis revealed down-regulation of farnesoid-X-receptor and other lipid pathways in ICC relative to HCC, and up-regulation of glycolytic pathways and GLUT-1 by HIF1α. These results imply limited utility of 18F-fluorocholine in ICC, however, significant metabolic differences between ICC, HCC, and parenchymal liver tissue may still provide clues about the underlying liver pathology. Gene and protein expression analysis support hyperglycolysis as a more dominant metabolic trait of ICC. PMID:27069767

  9. Quantitative evaluation of the memory bias effect in ROC studies with PET/CT

    NASA Astrophysics Data System (ADS)

    Kallergi, Maria; Pianou, Nicoletta; Georgakopoulos, Alexandros; Kafiri, Georgia; Pavlou, Spiros; Chatziioannou, Sofia

    2012-02-01

    PURPOSE. The purpose of the study was to evaluate the memory bias effect in ROC experiments with tomographic data and, specifically, in the evaluation of two different PET/CT protocols for the detection and diagnosis of recurrent thyroid cancer. MATERIALS AND METHODS. Two readers participated in an ROC experiment that evaluated tomographic images from 43 patients followed up for thyroid cancer recurrence. Readers evaluated first whole body PET/CT scans of the patients and then a combination of whole body and high-resolution head and neck scans of the same patients. The second set was read twice. Once within 48 hours of the first set and the second time at least a month later. The detection and diagnostic performances of the readers in the three reading sessions were assessed with the DBMMRMC and LABMRMC software using the area under the ROC curve as a performance index. Performances were also evaluated by comparing the number and the size of the detected abnormal foci among the three readings. RESULTS. There was no performance difference between first and second treatments. There were statistically significant differences between first and third, and second and third treatments showing that memory can seriously affect the outcome of ROC studies. CONCLUSION. Despite the fact that tomographic data involve numerous image slices per patient, the memory bias effect is present and substantial and should be carefully eliminated from analogous ROC experiments.

  10. Unusual Presentation of Bladder Paraganglioma: Comparison of (131)I MIBG SPECT/CT and (68)Ga DOTANOC PET/CT.

    PubMed

    Jain, Tarun Kumar; Basher, Rajender Kumar; Gupta, Nitin; Shukla, Jaya; Singh, Shrawan Kumar; Mittal, Bhagwant Rai

    2016-01-01

    Extraadrenal chromaffin cell-related tumors or paragangliomas are rare, especially in the bladder, accounting for less than 1% of cases. We report a 16-year-old boy who presented with hematuria and paroxysmal headache and was found to have a prostatic growth infiltrating the urinary bladder on anatomical imaging. Iodine-131 ((131)I) metaiodobenzylguanidine (MIBG) whole-body scanning and subsequently gallium-68 ((68)Ga) DOTANOC positron emission tomography/computed tomography (PET/CT) were performed. The MIBG scan revealed a non-tracer-avid soft-tissue mass, while DOTANOC PET/CT revealed a tracer-avid primary soft-tissue mass involving the urinary bladder and prostate with metastasis to the iliac lymph nodes. He underwent surgical management; histopathology of the surgical specimen revealed a bladder paraganglioma, whereas the prostate was found to be free of tumor.

  11. 18F-NaF and 18F-FDG PET/CT in Gorham-Stout Disease.

    PubMed

    Papadakis, Georgios Z; Millo, Corina; Bagci, Ulas; Blau, Jenny; Collins, Michael T

    2016-11-01

    Gorham-Stout disease (GSD) is an extremely rare skeletal disorder of unknown etiology characterized by benign proliferation of vascular or lymphatic channels, leading to progressive bone resorption. We report on a patient diagnosed with GSD affecting the right scapula and the right ribs, who underwent PET/CT scans using F-FDG and F-NaF. The remnant upper portion of the affected scapula did not show F-FDG uptake but demonstrated markedly increased F-NaF activity. Furthermore, intense F-NaF activity was seen on the right posterior ribs, which were actively being resorbed, suggesting the potential application of F-NaF-PET/CT imaging in GSD diagnosis and follow-up.

  12. Ectopic ACTH and CRH co-secreting tumor localized by 68Ga-DOTA-TATE PET/CT

    PubMed Central

    Papadakis, Georgios Z.; Bagci, Ulas; Sadowski, Samira M.; Patronas, Nicholas J.; Stratakis, Constantine A.

    2015-01-01

    Diagnosis of ectopic adrenocorticotropic hormone (ACTH) and corticotropin releasing hormone (CRH) co-secreting tumors causing Cushing syndrome (CS) is challenging, since these tumors are rare and their diagnosis is frequently confused with Cushing disease (CD), due to the effect of CRH on the pituitary. We report a case of a 21-year-old male who was referred to our institution with persistent hypercortisolemia and CS after undergoing unnecessary transsphenoidal surgery (TSS). 68Ga-DOTA-TATE PET/CT revealed increased tracer uptake in the thymus which was histologically proved to be neuroendocrine tumor (NET) staining positive for ACTH and CRH. Imaging with 18F-FDG PET/CT was not diagnostic. PMID:26018709

  13. Ectopic ACTH and CRH Co-secreting Tumor Localized by 68Ga-DOTA-TATE PET/CT.

    PubMed

    Papadakis, Georgios Z; Bagci, Ulas; Sadowski, Samira M; Patronas, Nicholas J; Stratakis, Constantine A

    2015-07-01

    Diagnosis of ectopic adrenocorticotropic hormone (ACTH) and corticotropin-releasing hormone (CRH) co-secreting tumors causing Cushing syndrome (CS) is challenging because these tumors are rare and their diagnosis is frequently confused with Cushing disease (CD), caused by the effect of CRH on the pituitary. We report a case of a 21-year-old male patient who was referred to our institution with persistent hypercortisolemia and CS after undergoing unnecessary transsphenoidal surgery (TSS). ⁶⁸Ga-DOTA-TATE PET/CT revealed increased tracer uptake in the thymus, which was histologically proven to be a neuroendocrine tumor (NET) that stained positive for ACTH and CRH. Imaging with ¹⁸F-FDG PET/CT was not diagnostic.

  14. F18-FDG-PET/CT for evaluation of intraductal papillary mucinous neoplasms (IPMN): a review of the literature.

    PubMed

    Bertagna, Francesco; Treglia, Giorgio; Baiocchi, Gian Luca; Giubbini, Raffaele

    2013-04-01

    Intraductal papillary mucinous neoplasms (IPMN) are intraductal mucin-producing neoplasms with tall columnar, mucin-containing epithelium, with or without papillary projections, involving the main pancreatic duct and/or major side branches. They account for approximately 25 % of all cystic neoplasms and can be subdivided into benign lesions, borderline lesions, and carcinoma. In this clinical scenario accurate preoperative diagnosis can eliminate unnecessary surgery, which is risky and potentially harmful, yet enable effective selection of patients who are candidates for surgery. In this review we try to provide a complete evaluation of the use of F18-FDG-PET/CT for diagnosis of this neoplasm on the basis of published papers. F18-FDG-PET/CT seems to be an useful technique for preoperative work-up of patients with suspected IPMN and is an improvement over conventional imaging in distinguishing benign from malignant lesions, especially for selecting patients for surgical treatment or for long-term follow-up.

  15. Unusual Presentation of Bladder Paraganglioma: Comparison of 131I MIBG SPECT/CT and 68Ga DOTANOC PET/CT

    PubMed Central

    Jain, Tarun Kumar; Basher, Rajender Kumar; Gupta, Nitin; Shukla, Jaya; Singh, Shrawan Kumar; Mittal, Bhagwant Rai

    2016-01-01

    Extraadrenal chromaffin cell-related tumors or paragangliomas are rare, especially in the bladder, accounting for less than 1% of cases. We report a 16-year-old boy who presented with hematuria and paroxysmal headache and was found to have a prostatic growth infiltrating the urinary bladder on anatomical imaging. Iodine-131 (131I) metaiodobenzylguanidine (MIBG) whole-body scanning and subsequently gallium-68 (68Ga) DOTANOC positron emission tomography/computed tomography (PET/CT) were performed. The MIBG scan revealed a non-tracer-avid soft-tissue mass, while DOTANOC PET/CT revealed a tracer-avid primary soft-tissue mass involving the urinary bladder and prostate with metastasis to the iliac lymph nodes. He underwent surgical management; histopathology of the surgical specimen revealed a bladder paraganglioma, whereas the prostate was found to be free of tumor. PMID:26912984

  16. Dual energy CT for attenuation correction with PET/CT

    SciTech Connect

    Xia, Ting; Alessio, Adam M.; Kinahan, Paul E.

    2014-01-15

    Purpose: The authors evaluate the energy dependent noise and bias properties of monoenergetic images synthesized from dual-energy CT (DECT) acquisitions. These monoenergetic images can be used to estimate attenuation coefficients at energies suitable for positron emission tomography (PET) and single-photon emission computed tomography (SPECT) imaging. This is becoming more relevant with the increased use of quantitative imaging by PET/CT and SPECT/CT scanners. There are, however, potential variations in the noise and bias of synthesized monoenergetic images as a function of energy. Methods: The authors used analytic approximations and simulations to estimate the noise and bias of synthesized monoenergetic images of water-filled cylinders with different shapes and the NURBS-based cardiac-torso (NCAT) phantom from 40 to 520 keV, the range of SPECT and PET energies. The dual-kVp spectra were based on the GE Lightspeed VCT scanner at 80 and 140 kVp with added filtration of 0.5 mm Cu. The authors evaluated strategies of noise suppression with sinogram smoothing and dose minimization with reduction of tube currents at the two kVp settings. The authors compared the impact of DECT-based attenuation correction with single-kVp CT-based attenuation correction on PET quantitation for the NCAT phantom for soft tissue and high-Z materials of bone and iodine contrast enhancement. Results: Both analytic calculations and simulations displayed the expected minimum noise value for a synthesized monoenergetic image at an energy between the mean energies of the two spectra. In addition the authors found that the normalized coefficient of variation in the synthesized attenuation map increased with energy but reached a plateau near 160 keV, and then remained constant with increasing energy up to 511 keV and beyond. The bias was minimal, as the linear attenuation coefficients of the synthesized monoenergetic images were within 2.4% of the known true values across the entire energy range

  17. Imaging Intratumoral Nanoparticle Uptake after Combining Nanoembolization with Various Ablative Therapies in Hepatic VX2 Rabbit Tumors

    PubMed Central

    Tam, Alda L; Melancon, Marites P.; Abdelsalam, Mohamed; Figueira, Tomas Appleton; Dixon, Katherine; McWatters, Amanda; Zhou, Min; Huang, Qian; Mawlawi, Osama; Dunner, Kenneth; Li, Chun; Gupta, Sanjay

    2016-01-01

    Combining image-guided therapy techniques for the treatment of liver cancers is a strategy that is being used to improve local tumor control rates. Here, we evaluate the intratumoral uptake of nanoparticles used in combination with radiofrequency ablation (RFA), irreversible electroporation (IRE), or laser induced thermal therapy (LITT). Eight rabbits with VX2 tumor in the liver underwent one of four treatments: (i) nanoembolization (NE) with radiolabeled, hollow gold nanoparticles loaded with doxorubicin (64Cu-PEG-HAuNS-DOX); (ii) NE+RFA; (iii) NE+IRE; (iv) NE+LITT. Positron emission tomography/computed tomography (PET/CT) imaging was obtained 1-hr or 18-hrs after intervention. Tissue samples were collected for autoradiography and transmission electron microscopy (TEM) analysis. PET/CT imaging at 1-hr showed focal deposition of oil and nanoparticles in the tumor only after NE+RFA but at 18-hrs, all animals had focal accumulation of oil and nanoparticles in the tumor region. Autoradiograph analysis demonstrated nanoparticle deposition in the tumor and in the ablated tissues adjacent to the tumor when NE was combined with ablation. TEM results showed the intracellular uptake of nanoparticles in tumor only after NE+IRE. Nanoparticles demonstrated a structural change, suggesting direct interaction, potentially leading to drug release, only after NE+LITT. The findings demonstrate that a combined NE and ablation treatment technique for liver tumors is feasible, resulting in deposition of nanoparticles in and around the tumor. Depending on the ablative energy applied, different effects are seen on nanoparticle localization and structure. These effects should be considered when designing nanoparticles for use in combination with ablation technologies. PMID:27305763

  18. Diagnostic Ability of FDG-PET/CT in the Detection of Malignant Pleural Effusion

    PubMed Central

    Nakajima, Reiko; Abe, Koichiro; Sakai, Shuji

    2015-01-01

    Abstract We investigated the role of F-18 fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) for the differential diagnosis of malignant and benign pleural effusion. We studied 36 consecutive patients with histologically proven cancer (excluding malignant mesothelioma) who underwent FDG-PET/CT for suspected malignant pleural effusion. Fourteen patients had cytologically proven malignant pleural effusion and the other 22 patients had either negative cytology or clinical follow-up, which confirmed the benign etiology. We examined the maximum standardized uptake values (SUVmax) of pleural effusion and the target-to-normal tissue ratio (TNR), calculated as the ratio of the pleural effusion SUVmax to the SUVmean of the normal tissues (liver, spleen, 12th thoracic vertebrae [Th12], thoracic aorta, and spinalis muscle). We also examined the size and density (in Hounsfield units) of the pleural effusion and pleural abnormalities on CT images. TNR (Th12) and increased pleural FDG uptake compared to background blood pool were significantly more frequent in cases with malignant pleural effusion (P < 0.05 for both). The cutoff TNR (Th12) value of >0.95 was the most accurate; the sensitivity, specificity, and accuracy for this value were 93%, 68%, and 75%, respectively. FDG-PET/CT can be a useful method for the differential diagnosis of malignant and benign pleural effusion. PMID:26200610

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

    NASA Astrophysics Data System (ADS)

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

    2013-02-01

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

  20. Potential of F-18 PET/CT in the Detection of Leptomeningeal Metastasis.

    PubMed

    Short, Ryan G; Bal, Susan; German, John P; Poelstra, Raymond J; Kardan, Arash

    2014-12-01

    Leptomeningeal metastasis (LM) is a rare but increasingly common condition in which malignant cells migrate to the meninges. The gold standard for diagnosing LM is detection of cancer cells in the cerebrospinal fluid (CSF). Contrast enhanced-magnetic resonance imaging (CE-MRI) is also used to diagnose LM. We describe a case of LM in which CE-MRI of the neuroaxis was initially negative for meningeal enhancement but F-18 fluorodeoxyglucose positron-emission tomography/computed tomography (F-18 FDG PET/CT) revealed hypermetabolism within the lumbar spinal canal. Positive F-18 FDG PET findings have rarely been reported in LM and, to our knowledge, have never been reported in the context of initially negative CE-MRI scanning of the neuroaxis. F-18 FDG PET/CT may represent an alternative modality for diagnosing LM in patients who are unable to undergo CE-MRI and/or LP or in patients for whom initial CE-MRI and/or LP are negative for LM.

  1. Persisting PET-CT lesion activity and M. tuberculosis mRNA after pulmonary tuberculosis cure

    PubMed Central

    Malherbe, Stephanus T.; Shenai, Shubhada; Ronacher, Katharina; Loxton, Andre G.; Dolganov, Gregory; Kriel, Magdalena; Van, Tran; Chen, Ray Y.; Warwick, James; Via, Laura E.; Song, Taeksun; Lee, Myungsun; Schoolnik, Gary; Tromp, Gerard; Alland, David; Barry, Clifton E.; Winter, Jill; Walzl, Gerhard

    2016-01-01

    The absence of a gold standard to determine when antibiotics have induced sterilizing cure confounds the development of new approaches to treat pulmonary tuberculosis (PTB). We detected PET-CT imaging response patterns consistent with active disease along with the presence of Mycobacterium tuberculosis mRNA in sputum and bronchoalveolar lavage samples in a substantial proportion of adult, HIV-negative PTB patients after standard 6-month treatment plus one year follow-up, including patients with a durable cure and others who later developed recurrent disease. The presence of MTB mRNA in the context of non-resolving and intensifying lesions on PET-CT might indicate ongoing transcription, suggesting that even apparently curative PTB treatment may not eradicate all organisms in most patients. This suggests an important complementary role for the immune response in maintaining a disease-free state. Sterilizing drugs or host-directed therapies and better treatment response markers are likely needed for the successful development of improved and shortened PTB treatment strategies. PMID:27595324

  2. The Use of PET-CT in the Assessment of Patients with Colorectal Carcinoma.

    PubMed

    O'Connor, Owen J; McDermott, Shanaugh; Slattery, James; Sahani, Dushyant; Blake, Michael A

    2011-01-01

    Colorectal cancer is the third most commonly diagnosed cancer, accounting for 53,219 deaths in 2007 and an estimated 146,970 new cases in the USA during 2009. The combination of FDG PET and CT has proven to be of great benefit for the assessment of colorectal cancer. This is most evident in the detection of occult metastases, particularly intra- or extrahepatic sites of disease, that would preclude a curative procedure or in the detection of local recurrence. FDG PET is generally not used for the diagnosis of colorectal cancer although there are circumstances where PET-CT may make the initial diagnosis, particularly with its more widespread use. In addition, precancerous adenomatous polyps can also be detected incidentally on whole-body images performed for other indications; sensitivity increases with increasing polyp size. False-negative FDG PET findings have been reported with mucinous adenocarcinoma, and false-positive findings have been reported due to inflammatory conditions such as diverticulitis, colitis, and postoperative scarring. Therefore, detailed evaluation of the CT component of a PET/CT exam, including assessment of the entire colon, is essential.

  3. Central Pontine Myelinolysis and Localized Fluorodeoxyglucose Uptake Seen on 18F-FDG PET/CT

    PubMed Central

    Rønne, Frederik; Tfelt-Hansen, Peer Carsten; Rørdam, Lene

    2017-01-01

    Case report describing the finding of central pontine myelinolysis (CPM) using combined fluorine-18 ( 18F)-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT). The patient was a known alcoholic who, during admission was under treatment for hyponatremia, showed a significant decline in both motor and cognitive function. Combined 18F-FDG PET/CT showed localized FDG uptake in the pons, consistent with the finding of CPM observed on magnetic resonance imaging (MRI). CPM is a demyelinating lesion of the pons, resulting in several neurological symptoms. The exact cause of CPM is not clear, but a strong relations between loss of myelin and osmotic stress exists, especially during rapid correction of hyponatremia. The osmotic stress is thought to induce disruption of the blood-brain barrier, allowing access for inflammatory mediators in extravascular brain tissue, which most likely attracts glial cells of the brain, attracts macrophages and activates astocytes. We suggest that metabolism in these activated cells could be responsible for the localized FDG uptake during active CPM. PMID:28217021

  4. Multimodal 3D PET/CT system for bronchoscopic procedure planning

    NASA Astrophysics Data System (ADS)

    Cheirsilp, Ronnarit; Higgins, William E.

    2013-02-01

    Integrated positron emission tomography (PET) / computed-tomography (CT) scanners give 3D multimodal data sets of the chest. Such data sets offer the potential for more complete and specific identification of suspect lesions and lymph nodes for lung-cancer assessment. This in turn enables better planning of staging bronchoscopies. The richness of the data, however, makes the visualization and planning process difficult. We present an integrated multimodal 3D PET/CT system that enables efficient region identification and bronchoscopic procedure planning. The system first invokes a series of automated 3D image-processing methods that construct a 3D chest model. Next, the user interacts with a set of interactive multimodal graphical tools that facilitate procedure planning for specific regions of interest (ROIs): 1) an interactive region candidate list that enables efficient ROI viewing in all tools; 2) a virtual PET-CT bronchoscopy rendering with SUV quantitative visualization to give a "fly through" endoluminal view of prospective ROIs; 3) transverse, sagittal, coronal multi-planar reformatted (MPR) views of the raw CT, PET, and fused CT-PET data; and 4) interactive multimodal volume/surface rendering to give a 3D perspective of the anatomy and candidate ROIs. In addition the ROI selection process is driven by a semi-automatic multimodal method for region identification. In this way, the system provides both global and local information to facilitate more specific ROI identification and procedure planning. We present results to illustrate the system's function and performance.

  5. AAPM Task Group 108: PET and PET/CT shielding requirements.

    PubMed

    Madsen, Mark T; Anderson, Jon A; Halama, James R; Kleck, Jeff; Simpkin, Douglas J; Votaw, John R; Wendt, Richard E; Williams, Lawrence E; Yester, Michael V

    2006-01-01

    The shielding of positron emission tomography (PET) and PET/CT (computed tomography) facilities presents special challenges. The 0.511 MeV annihilation photons associated with positron decay are much higher energy than other diagnostic radiations. As a result, barrier shielding may be required in floors and ceilings as well as adjacent walls. Since the patient becomes the radioactive source after the radiopharmaceutical has been administered, one has to consider the entire time that the subject remains in the clinic. In this report we present methods for estimating the shielding requirements for PET and PET/CT facilities. Information about the physical properties of the most commonly used clinical PET radionuclides is summarized, although the report primarily refers to fluorine-18. Typical PET imaging protocols are reviewed and exposure rates from patients are estimated including self-attenuation by body tissues and physical decay of the radionuclide. Examples of barrier calculations are presented for controlled and noncontrolled areas. Shielding for adjacent rooms with scintillation cameras is also discussed. Tables and graphs of estimated transmission factors for lead, steel, and concrete at 0.511 MeV are also included. Meeting the regulatory limits for uncontrolled areas can be an expensive proposition. Careful planning with the equipment vendor, facility architect, and a qualified medical physicist is necessary to produce a cost effective design while maintaining radiation safety standards.

  6. Gastrointestinal Stromal Tumor Showing Intense Tracer Uptake on PSMA PET/CT.

    PubMed

    Noto, Benjamin; Weckesser, Matthias; Buerke, Boris; Pixberg, Michaela; Avramovic, Nemanja

    2017-03-01

    A 70-year-old man with suspected prostate cancer was referred for Ga-PSMA-HBED-CC PET/CT (short PSMA PET/CT) for staging of tumor extent. Apart from vivid tracer uptake in the prostate gland and osseous metastasis, PSMA PET/CT revealed a large soft tissue mass with calcifications in the left upper abdomen showing intense tracer uptake. Histologic examination revealed the mass to be a gastrointestinal stromal tumor.

  7. From PET/CT to PET/MRI: advances in instrumentation and clinical applications.

    PubMed

    Hu, Zhenhua; Yang, Weidong; Liu, Haixiao; Wang, Kun; Bao, Chengpeng; Song, Tianming; Wang, Jing; Tian, Jie

    2014-11-03

    Multimodality imaging of positron emission tomography/computed tomography (PET/CT) provides both metabolic information and the anatomic structure, which is significantly superior to either PET or CT alone and has greatly improved its clinical applications. Because of the higher soft-tissue contrast of magnetic resonance imaging (MRI) and no extra ionizing radiation, PET/MRI imaging is the hottest topic currently. PET/MRI is swiftly making its way into clinical practice. However, it has many technical difficulties to overcome, such as photomultiplier tubes, which cannot work properly in a magnetic field, and the inability to provide density information on the object for attenuation correction. This paper introduces the technique process of PET/MRI and summarizes its clinical applications, including imaging in oncology, neurology, and cardiology.

  8. [PET/CT tomography. Usefulness in oncology].

    PubMed

    Martínez-Villaseñor, David; Gerson-Cwilich, Raquel

    2006-01-01

    In order to have optimum results in oncological patients, precise evaluation, diagnosis and staging of the patient is necessary. Positron emission tomography (PET) yields a high negative predictive value through exploration of the entire body. It diagnoses the benign or malignant state of a neoplasm that has been detected by other imaging methods and establishes an extensive diagnosis previous to therapeutic treatment of a known cancer. It identifies residual tumor and changes produced after surgery, chemotherapy or radiotherapy and locates suspicious residual tumor clinically or by elevation of the tumor markers. It allows for a new extension study or re-staging after diagnosis of recurrence and permits early evaluation of response to a therapeutic regime and permits the search for a primary tumor in patients with metastasis of unknown origin. PET leads to a molecular functional imaging of cancer in the entire body.

  9. 18F-FDG PET of the hands with a dedicated high-resolution PEM system (arthro-PET): correlation with PET/CT, radiography and clinical parameters

    PubMed Central

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

    2015-01-01

    Purpose The aim of this study was to prospectively determine the feasibility and compare the novel use of a positron emission mammography (PEM) scanner with standard PET/CT for evaluating hand osteoarthritis (OA) with 18F-FDG. Methods Institutional review board approval and written informed consent were obtained for this HIPAA-compliant prospective study in which 14 adults referred for oncological 18F-FDG PET/CT underwent dedicated hand PET/CT followed by arthro-PET using the PEM device. Hand radiographs were obtained and scored for the presence and severity of OA. Summed qualitative and quantitative joint glycolytic scores for each modality were compared with the findings on plain radiography and clinical features. Results Eight patients with clinical and/or radiographic evidence of OA comprised the OA group (mean age 73±7.7 years). Six patients served as the control group (53.7±9.3 years). Arthro-PET quantitative and qualitative joint glycolytic scores were highly correlated with PET/CT findings in the OA patients (r=0.86. p =0.007; r=0.94, p=0.001). Qualitative arthro-PET and PET/CT joint scores were significantly higher in the OA patients than in controls (38.7±6.6 vs. 32.2±0.4, p=0.02; 37.5±5.4 vs. 32.2±0.4, p=0.03, respectively). Quantitative arthro-PET and PET/CT maximum SUV-lean joint scores were higher in the OA patients, although they did not reach statistical significance (20.8±4.2 vs. 18±1.8, p= 0.13; 22.8±5.38 vs. 20.1±1.54, p=0.21). By definition, OA patients had higher radiographic joint scores than controls (30.9±31.3 vs. 0, p=0.03). Conclusion Hand imaging using a small field of view PEM system (arthro-PET) with FDG is feasible, performing comparably to PET/CT in assessing metabolic joint activity. Arthro-PET and PET/CT showed higher joint FDG uptake in OA. Further exploration of arthro-PET in arthritis management is warranted. PMID:25134669

  10. 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

  11. The role of FDG PET/CT in evaluation of mediastinal masses and neurogenic tumors of chest wall

    PubMed Central

    Tatci, Ebru; Ozmen, Ozlem; Dadali, Yeliz; Biner, Inci Uslu; Gokcek, Atila; Demirag, Funda; Incekara, Funda; Arslan, Nuri

    2015-01-01

    We evaluated the efficiency of FDG PET/CT for the differentiation of malignant from benign mediastinal masses and neurogenic tumors of chest-wall. Methods: The 88 patients with chest wall-mediastinal masses who underwent examination before operation were retrospectively reviewed. Size, CT density (HU mean) and SUVmax of mediastinal and chest wall lesions were determined. Statistical differences of these parameters were compared between groups by Mann-Whitney U test. Receiver-operating characteristic curve (ROC) analysis with respect to SUVmax was performed to determine the best cutoff value for differentiating benign from malignant masses. Results: The overall sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) of PET/CT in detection of malignancy were 90%, 55.17%, 67%, 50.94% and 91.43%, respectively. The SUVmax, HU mean and size were higher in malignant cases (P < 0.05). To distinguish benign and malignant lesions, the cut off value of SUVmax was 4.67. The lesion SUVmax was significantly associated with the lesion size and lesion HU mean values (P < 0.05). The value of SUVmax and HU mean were higher in solid benign lesions than those of cystic benign lesions (P < 0.05). The lesion size was higher in cystic lesions (P = 0.000). The mean SUVmax was significantly higher in invasive thymomas than those of non-invasive forms (P = 0.029). Conclusion: FDG PET/CT may be complementary to conventional imaging methods for the evaluation of mediastinal and chest wall masses. PET/CT may reduce unnecessary invasive investigations for diagnosis in patients with nonavid or low avid FDG lesions. However confirmatory tissue sampling is required to confirm PET positive findings for the definite diagnosis. PMID:26379916

  12. Ultralow dose computed tomography attenuation correction for pediatric PET CT using adaptive statistical iterative reconstruction

    SciTech Connect

    Brady, Samuel L.; Shulkin, Barry L.

    2015-02-15

    Purpose: To develop ultralow dose computed tomography (CT) attenuation correction (CTAC) acquisition protocols for pediatric positron emission tomography CT (PET CT). Methods: A GE Discovery 690 PET CT hybrid scanner was used to investigate the change to quantitative PET and CT measurements when operated at ultralow doses (10–35 mA s). CT quantitation: noise, low-contrast resolution, and CT numbers for 11 tissue substitutes were analyzed in-phantom. CT quantitation was analyzed to a reduction of 90% volume computed tomography dose index (0.39/3.64; mGy) from baseline. To minimize noise infiltration, 100% adaptive statistical iterative reconstruction (ASiR) was used for CT reconstruction. PET images were reconstructed with the lower-dose CTAC iterations and analyzed for: maximum body weight standardized uptake value (SUV{sub bw}) of various diameter targets (range 8–37 mm), background uniformity, and spatial resolution. Radiation dose and CTAC noise magnitude were compared for 140 patient examinations (76 post-ASiR implementation) to determine relative dose reduction and noise control. Results: CT numbers were constant to within 10% from the nondose reduced CTAC image for 90% dose reduction. No change in SUV{sub bw}, background percent uniformity, or spatial resolution for PET images reconstructed with CTAC protocols was found down to 90% dose reduction. Patient population effective dose analysis demonstrated relative CTAC dose reductions between 62% and 86% (3.2/8.3–0.9/6.2). Noise magnitude in dose-reduced patient images increased but was not statistically different from predose-reduced patient images. Conclusions: Using ASiR allowed for aggressive reduction in CT dose with no change in PET reconstructed images while maintaining sufficient image quality for colocalization of hybrid CT anatomy and PET radioisotope uptake.

  13. 18F-FDG PET/CT and PET/MRI Perform Equally Well in Cancer: Evidence from Studies on More Than 2,300 Patients

    PubMed Central

    Spick, Claudio; Herrmann, Ken; Czernin, Johannes

    2016-01-01

    18F-FDG PET/CT has become the reference standard in oncologic imaging against which the performance of other imaging modalities is measured. The promise of PET/MRI includes multiparametric imaging to further improve diagnosis and phenotyping of cancer. Rather than focusing on these capabilities, many investigators have examined whether 18F-FDG PET combined with mostly anatomic MRI improves cancer staging and restaging. After a description of PET/MRI scanner designs and a discussion of technical and operational issues, we review the available literature to determine whether cancer assessments are improved with PET/MRI. The available data show that PET/MRI is feasible and performs as well as PET/CT in most types of cancer. Diagnostic advantages may be achievable in prostate cancer and in bone metastases, whereas disadvantages exist in lung nodule assessments. We conclude that 18F-FDG PET/MRI and PET/CT provide comparable diagnostic information when MRI is used simply to provide the anatomic framework. Thus, PET/MRI could be used in lieu of PET/CT if this approach becomes economically viable and if reasonable workflows can be established. Future studies should explore the multiparametric potential of MRI. PMID:26742709

  14. Role of fluorine-18 fluorodeoxyglucose PET/CT in head and neck oncology: the point of view of the radiation oncologist.

    PubMed

    Cacicedo, Jon; Navarro, Arturo; Del Hoyo, Olga; Gomez-Iturriaga, Alfonso; Alongi, Filippo; Medina, Jose A; Elicin, Olgun; Skanjeti, Andrea; Giammarile, Francesco; Bilbao, Pedro; Casquero, Francisco; de Bari, Berardino; Dal Pra, Alan

    2016-11-01

    Squamous cell carcinoma is the most common malignant tumour of the head and neck. The initial TNM staging, the evaluation of the tumour response during treatment, and the long-term surveillance are crucial moments in the approach to head and neck squamous cell carcinoma (HNSCC). Thus, at each of these moments, the choice of the best diagnostic tool providing the more precise and larger information is crucial. Positron emission tomography with fluorine-18 fludeoxyglucose integrated with CT ((18)F-FDG-PET/CT) rapidly gained clinical acceptance, and it has become an important imaging tool in routine clinical oncology. However, controversial data are currently available, for example, on the role of (18)F-FDG-PET/CT imaging during radiotherapy planning, the prognostic value or its real clinical impact on treatment decisions. In this article, the role of (18)F-FDG-PET/CT imaging in HNSCC during pre-treatment staging, radiotherapy planning, treatment response assessment, prognosis and follow-up is reviewed focusing on current evidence and controversial issues. A proposal on how to integrate (18)F-FDG-PET/CT in daily clinical practice is also described.

  15. SU-E-CAMPUS-I-06: Y90 PET/CT for the Instantaneous Determination of Both Target and Non-Target Absorbed Doses Following Hepatic Radioembolization

    SciTech Connect

    Pasciak, A; Kao, J

    2014-06-15

    Purpose The process of converting Yttrium-90 (Y90) PET/CT images into 3D absorbed dose maps will be explained. The simple methods presented will allow the medical physicst to analyze Y90 PET images following radioembolization and determine the absorbed dose to tumor, normal liver parenchyma and other areas of interest, without application of Monte-Carlo radiation transport or dose-point-kernel (DPK) convolution. Methods Absorbed dose can be computed from Y90 PET/CT images based on the premise that radioembolization is a permanent implant with a constant relative activity distribution after infusion. Many Y90 PET/CT publications have used DPK convolution to obtain 3D absorbed dose maps. However, this method requires specialized software limiting clinical utility. The Local Deposition method, an alternative to DPK convolution, can be used to obtain absorbed dose and requires no additional computer processing. Pixel values from regions of interest drawn on Y90 PET/CT images can be converted to absorbed dose (Gy) by multiplication with a scalar constant. Results There is evidence that suggests the Local Deposition method may actually be more accurate than DPK convolution and it has been successfully used in a recent Y90 PET/CT publication. We have analytically compared dose-volume-histograms (DVH) for phantom hot-spheres to determine the difference between the DPK and Local Deposition methods, as a function of PET scanner point-spread-function for Y90. We have found that for PET/CT systems with a FWHM greater than 3.0 mm when imaging Y90, the Local Deposition Method provides a more accurate representation of DVH, regardless of target size than DPK convolution. Conclusion Using the Local Deposition Method, post-radioembolization Y90 PET/CT images can be transformed into 3D absorbed dose maps of the liver. An interventional radiologist or a Medical Physicist can perform this transformation in a clinical setting, allowing for rapid prediction of treatment efficacy by

  16. Adapted Treatment Guided by Interim PET-CT Scan in Advanced Hodgkin’s Lymphoma

    PubMed Central

    Johnson, Peter; Federico, Massimo; Kirkwood, Amy; Fosså, Alexander; Berkahn, Leanne; Carella, Angelo; d’Amore, Francesco; Enblad, Gunilla; Franceschetto, Antonella; Fulham, Michael; Luminari, Stefano; O’Doherty, Michael; Patrick, Pip; Roberts, Thomas; Sidra, Gamal; Stevens, Lindsey; Smith, Paul; Trotman, Judith; Viney, Zaid; Radford, John; Barrington, Sally

    2016-01-01

    Background We tested interim positron-emission tomography–computed tomography (PET-CT) as a measure of early response to chemotherapy in order to guide treatment for patients with advanced Hodgkin’s lymphoma. Methods Patients with newly diagnosed advanced classic Hodgkin’s lymphoma underwent a baseline PET-CT scan, received two cycles of ABVD (doxorubicin, bleomycin, vinblastine, and dacarbazine) chemotherapy, and then underwent an interim PET-CT scan. Images were centrally reviewed with the use of a 5-point scale for PET findings. Patients with negative PET findings after two cycles were randomly assigned to continue ABVD (ABVD group) or omit bleomycin (AVD group) in cycles 3 through 6. Those with positive PET findings after two cycles received BEACOPP (bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone). Radiotherapy was not recommended for patients with negative findings on interim scans. The primary outcome was the difference in the 3-year progression-free survival rate between randomized groups, a noninferiority comparison to exclude a difference of 5 or more percentage points. Results A total of 1214 patients were registered; 937 of the 1119 patients (83.7%) who underwent an interim PET-CT scan according to protocol had negative findings. With a median follow-up of 41 months, the 3-year progression-free survival rate and overall survival rate in the ABVD group were 85.7% (95% confidence interval [CI], 82.1 to 88.6) and 97.2% (95% CI, 95.1 to 98.4), respectively; the corresponding rates in the AVD group were 84.4% (95% CI, 80.7 to 87.5) and 97.6% (95% CI, 95.6 to 98.7). The absolute difference in the 3-year progression-free survival rate (ABVD minus AVD) was 1.6 percentage points (95% CI, −3.2 to 5.3). Respiratory adverse events were more severe in the ABVD group than in the AVD group. BEACOPP was given to the 172 patients with positive findings on the interim scan, and 74.4% had negative findings on a third

  17. Increased (18)F-fluorodeoxyglucose uptake in benign, nonphysiologic lesions found on whole-body positron emission tomography/computed tomography (PET/CT): accumulated data from four years of experience with PET/CT.

    PubMed

    Metser, Ur; Even-Sapir, Einat

    2007-05-01

    The use of (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG-PET) in the field of oncology is rapidly evolving; however, (18)F-FDG is not tumor specific. Aside from physiological uptake (18)F-FDG also may accumulate in benign processes. Knowledge of these (18)F-FDG-avid nonmalignant lesions is essential for accurate PET interpretation in oncologic patients to avoid a false-positive interpretation. Through the systematic review of the reports of PET/computed tomography (CT) studies performed in oncologic patients during a 6-month period, we found benign nonphysiological uptake of (18)F-FDG in more than 25% of studies. In half of these, (18)F-FDG uptake was moderate or marked in intensity, similar to that of malignant sites. A total of 73% of benign lesions were inflammatory in nature, with post-traumatic bone and soft-tissue abnormalities (including iatrogenic injury) and benign tumors accounting for the remainder. The differentiation of benign from malignant uptake of (18)F-FDG on PET alone may be particularly challenging as a result of the low anatomical resolution of PET and paucity of anatomical landmarks. Fusion imaging, namely PET/CT, has been shown to improve not only the sensitivity of PET interpretation but also its specificity. Aside from better anatomical localization of lesions on PET/CT, morphological characterization of lesions on CT often may improve the diagnostic accuracy of nonspecific (18)F-FDG uptake. Correlation with CT on fused PET/CT data may obviate the need for further evaluation or biopsy in more than one-third of scintigraphic equivocal lesions. Familiarity with (18)F-FDG-avid nonmalignant lesions also may extend the use of (18)F-FDG-PET imaging beyond the field of oncology. We have tabulated our experience with benign entities associated with increased (18)F-FDG uptake on whole-body PET/CT from 12,000 whole-body (18)F-FDG-PET/CT studies performed during a 4-year period.

  18. FDG PET/CT findings of common bile duct tuberculosis.

    PubMed

    Dong, Aisheng; Wang, Yang; Gong, Jing; Zuo, Changjing

    2014-01-01

    Common bile duct (CBD) tuberculosis is rare. A 39-year-old woman was referred because of a 5-month history of abdominal pain. Abdominal enhanced MRI and CT showed dilatation of the distal CBD with irregularly thickened wall. Enhanced CT revealed enlarged retroperitoneal lymph nodes. FDG PET/CT showed increased FDG uptake of the CBD lesion and several retroperitoneal lymph nodes with slight FDG uptake. CBD cholangiocarcinoma with retroperitoneal lymph node metastasis was suspected. CBD tuberculosis was confirmed by endoluminal biopsy. Tuberculosis should be considered in the differential diagnosis of abnormal biliary FDG accumulation, particularly in tuberculosis endemic areas.

  19. The application of positron emission tomography (PET/CT) in diagnosis of breast cancer. Part II. Diagnosis after treatment initiation, future perspectives

    PubMed Central

    Jodłowska, Elżbieta; Czarnywojtek, Agata; Rewers, Amanda; Jarząbek, Grażyna; Kędzia, Witold; Ruchała, Marek

    2016-01-01

    Similarly to the applications described in the first part of this publication, positron emission tomography with computed tomography (PET/CT) is also gaining importance in monitoring a tumour's response to therapy and diagnosing breast cancer recurrences. This is additionally caused by the fact that many new techniques (dual-time point imaging, positron emission tomography with magnetic resonance PET/MR, PET/CT mammography) and radiotracers (16α-18F-fluoro-17β-estradiol, 18F-fluorothymidine) are under investigation. The highest sensitivity and specificity when monitoring response to treatment is achieved when the PET/CT scan is made after one or two chemotherapy courses. Response to anti-hormonal treatment can also be monitored, also when new radiotracers, such as FES, are used. When monitoring breast cancer recurrences during follow-up, PET/CT has higher sensitivity than conventional imaging modalities, making it possible to monitor the whole body simultaneously. New techniques and radiotracers enhance the sensitivity and specificity of PET and this is why, despite relatively high costs, it might become more widespread in monitoring response to treatment and breast cancer recurrences. PMID:27647983

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

    PubMed Central

    Ayaz, Sevin; Ayaz, Ümit Yaşar

    2016-01-01

    Summary Background We aimed to present unusual cranial FDG PET/CT findings of a 56-year-old female with multiple myeloma (MM). Case Report Plain CT images revealed a lytic lesion in the right parietal bone, filled with an oval-shaped, large, extra-axial, extradural, intracranial mass which measured 75×75×40 mm and had smooth borders. The right parietal lobe was compressed by the mass. The maximum standardized uptake value (SUVmax) of the mass lesion was 8.94 on FDG PET/CT images. Multiple lytic lesions with an increased uptake were also detected in other calvarial bones, in several vertebras and in the proximal left femur. After seven months, a control FDG PET/CT following radiotherapy and chemotherapy revealed almost complete regression of the right parietal extra-axial mass lesion. The number, size and metabolism of lytic lesions in other bones also decreased. Conclusions FDG PET/CT was useful for an initial evaluation of MM lesions and was effective in monitoring the response of these lesions to therapy. PMID:28058074

  1. 18F-fluorothymidine PET/CT as an early predictor of tumor response to treatment with cetuximab in human lung cancer xenografts.

    PubMed

    Takeuchi, Satoshi; Zhao, Songji; Kuge, Yuji; Zhao, Yan; Nishijima, Ken-Ichi; Hatano, Toshiyuki; Shimizu, Yasushi; Kinoshita, Ichiro; Tamaki, Nagara; Dosaka-Akita, Hirotoshi

    2011-09-01

    We investigated whether 18F-fluorothymidine-positron-emission tomography/computed tomography (18F-FLT-PET/CT) is useful for the evaluation of the very early response to anti-epidermal growth factor receptor (EGFR) antibody cetuximab therapy in human lung cancer xenografts. A human tumor xenograft model was established with a human non-small cell lung cancer cell line. The mice were randomly assigned to four groups: tumor growth follow-up, ex vivo study, PET/CT imaging and non-treated control. Mice were administered saline as control or cetuximab on day 1. An immunohistochemical study with Ki-67 was performed. Tumor volume treated with cetuximab was kept significantly smaller than control after day 8, although there was no difference on day 3. On day 3, 18F-FLT distribution was higher in the tumor than in other tissues, and was significantly decreased by treatment with cetuximab. On PET/CT imaging, 18F-FLT distribution in the tumor was clearly visualized, and the maximum standardized uptake value (SUV) was significantly decreased after treatment with cetuximab (p<0.01). Ki-67 expression was also significantly decreased on day 3 (p=0.01). These results suggest that 18F-FLT-PET/CT can be a useful predictor to determine the response to molecular targeted drugs such as cetuximab at an earlier time point than the change of tumor size.

  2. Comparison of an alternative and existing binning methods to reduce the acquisition duration of 4D PET/CT

    SciTech Connect

    Didierlaurent, David Ribes, Sophie; Caselles, Olivier; Jaudet, Cyril; Dierickx, Lawrence O.; Zerdoud, Slimane; Brillouet, Severine; Weits, Kathleen; Batatia, Hadj; Courbon, Frédéric

    2014-11-01

    Purpose: Respiratory motion is a source of artifacts that reduce image quality in PET. Four dimensional (4D) PET/CT is one approach to overcome this problem. Existing techniques to limiting the effects of respiratory motions are based on prospective phase binning which requires a long acquisition duration (15–25 min). This time is uncomfortable for the patients and limits the clinical exploitation of 4D PET/CT. In this work, the authors evaluated an existing method and an alternative retrospective binning method to reduce the acquisition duration of 4D PET/CT. Methods: The authors studied an existing mixed-amplitude binning (MAB) method and an alternative binning method by mixed-phases (MPhB). Before implementing MPhB, they analyzed the regularity of the breathing patterns in patients. They studied the breathing signal drift and missing CT slices that could be challenging for implementing MAB. They compared the performance of MAB and MPhB with current binning methods to measure the maximum uptake, internal volume, and maximal range of tumor motion. Results: MPhB can be implemented depending on an optimal phase (in average, the exhalation peak phase −4.1% of the entire breathing cycle duration). Signal drift of patients was in average 35% relative to the breathing amplitude. Even after correcting this drift, MAB was feasible in 4D CT for only 64% of patients. No significant differences appeared between the different binning methods to measure the maximum uptake, internal volume, and maximal range of tumor motion. The authors also determined the inaccuracies of MAB and MPhB to measure the maximum amplitude of tumor motion with three bins (less than 3 mm for movement inferior to 12 mm, up to 6.4 mm for a 21 mm movement). Conclusions: The authors proposed an alternative binning method by mixed-phase binning that halves the acquisition duration of 4D PET/CT. Mixed-amplitude binning was challenging because of signal drift and missing CT slices. They showed that more

  3. Lymph Node Metastasis from Tall-Cell Thyroid Cancer Negative on 18F-FDG PET/CT and Detected by 18F-Choline PET/CT.

    PubMed

    Piccardo, Arnoldo; Massollo, Michela; Bandelloni, Roberto; Arlandini, Anselmo; Foppiani, Luca

    2015-08-01

    A 77-year-old woman underwent thyroidectomy and (131)I remnant ablation for tall-cell differentiated cancer (DTC) of the left lobe. Detectable Tg levels (4.1 μg/L) under TSH suppression, with undetectable serum Tg-antibody levels, prompted neck ultrasonography, which revealed a lymph node in the left laterocervical region and in the right retroclavicular region. (18)F-FDG PET/CT showed uptake by the left lymph node. (18)F-choline PET/CT showed increased uptake by both lymph nodes. Histopathology revealed DTC solid metastasis in the left lymph node and solid and cystic metastasis in the right one. (18)F-choline PET/CT can locate virulent DTC recurrence, thereby increasing (18)F-FDG PET/CT information.

  4. Lymph nodes can accurately be measured on PET-CT for lymphoma staging/restaging without a concomitant contrast enhanced CT scan.

    PubMed

    Simpson, William L; Lee, Karen M; Sosa, Ninoska; Cooper, Nancy; Scigliano, Eileen; Brody, Joshua D; Doucette, John T; Kostakoglu, Lale

    2016-05-01

    Dual imaging with both contrast enhanced CT scan and PET-CT is recommended for evaluation of lymphoma. We compared the performance in identification and size measurements of involved lymph nodes in FDG-avid lymphomas on the low dose non-contrast enhanced CT of a PET-CT scan with those on a diagnostic contrast enhanced CT scan. The size of FDG-avid lymph nodes was measured in both the short and long axis on both the low dose non-contrast CT of the PET-CT and the contrast enhanced CT by two independent readers. A total of 307 FGD avid lymph nodes were identified in 52 patients. There was no statistically significant differences in the measured size of the nodes on the non-contrast and contrast enhanced scans (p=0.21). Baseline staging and restaging of FDG-avid lymphomas can be performed with one test, PET-CT, without an accompanying contrast enhanced CT scan, with no effect on the measured nodal size.

  5. 18F-FLT and 18F-FDG PET/CT in Predicting Response to Chemoradiotherapy in Nasopharyngeal Carcinoma: Preliminary Results

    PubMed Central

    Qi, Shi; Zhongyi, Yang; Yingjian, Zhang; Chaosu, Hu

    2017-01-01

    The purpose of this study was to explore the feasibility of 18F-Fluorothymidine (18F-FLT) and 18F-Fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) in predicting treatment response of nasopharyngeal carcinoma (NPC). Patients with NPC of Stage II-IVB were prospectively enrolled, receiving 2 cycles of neoadjuvant chemotherapy (NACT), followed by concurrent chemoradiotherapy. Each patient underwent pretreatment and post-NACT FLT PET/CT and FDG PET/CT. Standard uptake values (SUV) and tumor volume were measured. Tumor response to NACT was evaluated before radiotherapy by MRI (magnetic resonance imaging), and tumor regression at the end of radiotherapy was evaluated at 55 Gy, according to RECIST 1.1 Criteria. Finally, 20 patients were consecutively enrolled. At the end of radiotherapy, 7 patients reached complete regression while others were partial regression. After 2 cycles of NACT both FLT and FDG parameters declined remarkably. Parameters of FDG PET were more strongly correlated to tumor regression than those of FLT PET.70% SUVmax was the best threshold to define contouring margin around the target. Some residual lesions after NACT showed by MRI were negative in PET/CT. Preliminary results showed both 18F-FDG and 18F-FLT PET have the potential to monitor and predict tumor regression. PMID:28091565

  6. Design of respiration averaged CT for attenuation correction of the PET data from PET/CT

    SciTech Connect

    Chi, Pai-Chun Melinda; Mawlawi, Osama; Nehmeh, Sadek A.; Erdi, Yusuf E.; Balter, Peter A.; Luo, Dershan; Mohan, Radhe; Pan Tinsu

    2007-06-15

    Our previous patient studies have shown that the use of respiration averaged computed tomography (ACT) for attenuation correction of the positron emission tomography (PET) data from PET/CT reduces the potential misalignment in the thorax region by matching the temporal resolution of the CT to that of the PET. In the present work, we investigated other approaches of acquiring ACT in order to reduce the CT dose and to improve the ease of clinical implementation. Four-dimensional CT (4DCT) data sets for ten patients (17 lung/esophageal tumors) were acquired in the thoracic region immediately after the routine PET/CT scan. For each patient, multiple sets of ACTs were generated based on both phase image averaging (phase approach) and fixed cine duration image averaging (cine approach). In the phase approach, the ACTs were calculated from CT images corresponding to the significant phases of the respiratory cycle: ACT{sub 050phs} from end-inspiration (0%) and end-expiration (50%), ACT{sub 2070phs} from mid-inspiration (20%) and mid-expiration (70%), ACT{sub 4phs} from 0%, 20%, 50% and 70%, and ACT{sub 10phs} from all ten phases, which was the original approach. In the cine approach, which does not require 4DCT, the ACTs were calculated based on the cine images from cine durations of 1 to 6 s at 1 s increments. PET emission data for each patient were attenuation corrected with each of the above mentioned ACTs and the tumor maximum standard uptake value (SUV{sub max}), average SUV (SUV{sub avg}), and tumor volume measurements were compared. Percent differences were calculated between PET data corrected with various ACTs and that corrected with ACT{sub 10phs}. In the phase approach, the ACT{sub 10phs} can be approximated by the ACT{sub 4phs} to within a mean percent difference of 2% in SUV and tumor volume measurements. In cine approach, ACT{sub 10phs} can be approximated to within a mean percent difference of 3% by ACTs computed from cine durations {>=}3 s. Acquiring CT

  7. External ultrasonography of the neck does not add diagnostic value to integrated positron emission tomography-computed tomography (PET-CT) scanning in the diagnosis of cervical lymph node metastases in patients with esophageal carcinoma.

    PubMed

    Blom, R L G M; Vliegen, R F A; Schreurs, W M J; Belgers, H J; Stohr, I; Oostenbrug, L E; Sosef, M N

    2012-08-01

    One of the objectives of preoperative imaging in esophageal cancer patients is the detection of cervical lymph node metastases. Traditionally, external ultrasonography of the neck has been combined with computed tomography (CT) in order to improve the detection of cervical metastases. In general, integrated positron emission tomography-computed tomography (PET-CT) has been shown to be superior to CT or PET regarding staging and therefore may limit the role of external ultrasonography of the neck. The objective of this study was to determine the additional value of external ultrasonography of the neck to PET-CT. This study included all patients referred our center for treatment of esophageal carcinoma. Diagnostic staging was performed to determine treatment plan. Cervical lymph nodes were evaluated by external ultrasonography of the neck and PET-CT. In case of suspect lymph nodes on external ultrasonography or PET-CT, fine needle aspiration (FNA) was performed. Between 2008 and 2010, 170 out of 195 referred patients underwent both external ultrasonography of the neck and PET-CT. Of all patients, 84% were diagnosed with a tumor at or below the distal esophagus. In 140 of 170 patients, the cervical region was not suspect; no FNA was performed. Seven out of 170 patients had suspect nodes on both PET-CT and external ultrasonography. Five out of seven patients had cytologically confirmed malignant lymph nodes, one of seven had benign nodes, in one patient FNA was not performed; exclusion from esophagectomy was based on intra-abdominal metastases. In one out of 170 patients, PET-CT showed suspect nodes combined with a negative external ultrasonography; cytology of these nodes was benign. Twenty-two out of 170 patients had a negative PET-CT with suspect nodes on external ultrasonography. In 18 of 22 patients, cervical lymph nodes were cytologically confirmed benign; in four patients, FNA was not possible or inconclusive. At a median postoperative follow-up of 15 months

  8. Glucagon-Like Peptide-1 Receptor PET/CT with 68Ga-NOTA-Exendin-4 for Detecting Localized Insulinoma: A Prospective Cohort Study

    PubMed Central

    Luo, Yaping; Pan, Qingqing; Yao, Shaobo; Yu, Miao; Wu, Wenming; Xue, Huadan; Kiesewetter, Dale O.; Zhu, Zhaohui; Li, Fang; Zhao, Yupei; Chen, Xiaoyuan

    2017-01-01

    Preoperative localization of insulinoma is a clinical dilemma. We aimed to investigate whether glucagon-like peptide-1 receptor (GLP-1R) PET/CT with 68Ga-NOTA-MAL-cys40-exendin-4 (68Ga-NOTA-exendin-4) is efficient in detecting insulinoma. Methods In our prospective cohort study, patients with endogenous hyperinsulinemic hypoglycemia were enrolled. CT, MRI, endoscopic ultrasound, and 99mTc-hydrazinonicotinamide-TOC SPECT/CT were done according to standard protocols. GLP-1R PET/CT was performed 30–60 min after the injection of 68Ga-NOTA-exendin-4. The gold standard for diagnosis was the histopathologic results after surgery. Results Of 52 recruited patients, 43 patients with histopathologically proven insulinomas were included for the imaging studies. Nine patients did not undergo surgical intervention. 68Ga-NOTA-exendin-4 PET/CT correctly detected insulinomas in 42 of 43 patients with high tumor uptake (mean SUVavg ± SD, 10.2 ± 4.9; mean SUVmax ± SD, 23.6 ± 11.7), resulting in sensitivity of 97.7%. In contrast, 99mTc-hydrazinonicotinamide-TOC SPECT/CT showed a low sensitivity of 19.5% (8/41) in this group of patients; however, it successfully localized the tumor that was false-negative with GLP-1R PET/CT. The sensitivities of CT, MR, and endoscopic ultrasonography were 74.4% (32/43), 56.0% (14/25), and 84.0% (21/25), respectively. Conclusion 68Ga-NOTA-exendin-4 PET/CT is a highly sensitive imaging technique for the localization of insulinoma. PMID:26795291

  9. Cerebral Toxoplasmosis in a Patient with AIDS on F-18 FDG PET/CT.

    PubMed

    Kim, Hae Won; Won, Kyoung Sook; Choi, Byung Wook; Zeon, Seok Kil

    2010-04-01

    The distinction between primary central nervous system (CNS) lymphoma and nonmalignant lesions due to opportunistic infections, in particular cerebral toxoplasmosis, is important because of the different treatments involved. A 32-year-old patient with AIDS was hospitalized for intermittent headaches. Brain magnetic resonance imaging (MRI) showed a small well-enhanced nodular lesion in the right frontal lobe. A fluorine-18 fluorodeoxyglucose (F-18 FDG) positron emission tomography (PET)/computed tomography (CT) scan showed moderate FDG uptake in the nodular lesion of the right frontal lobe. We present a case of cerebral toxoplasmosis in a patient with acquired immunodeficiency syndrome (AIDS) and the usefulness of F-18 FDG PET/CT in the differential diagnosis of the cerebral toxoplasmosis will be discussed.

  10. Vertebral Hemangioma Mimicking Bone Metastasis in 68Ga-PSMA Ligand PET/CT.

    PubMed

    Artigas, Carlos; Otte, François-Xavier; Lemort, Marc; van Velthoven, Roland; Flamen, Patrick

    2017-05-01

    Ga-PSMA PET/CT was performed in a 68-year-old man to evaluate recurrent prostate cancer due to elevated serum prostate-specific antigen level. Images showed a focal uptake in the prostatic gland, suggesting local relapse, and an intense uptake in the 12th thoracic vertebra, with no morphological abnormalities in CT slices. In order to confirm extraprostatic disease and before radiotherapy planning, a full-spine MRI was performed, resulting with the morphological pattern of a vertebral hemangioma. Hystological analysis confirmed the local relapse in the prostate. No radiotherapy treatment was given to the vertebra, and after 1 year of follow-up without systemic treatment, prostate-specific antigen is still undetectable.

  11. 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.

  12. [Extension study and evaluation of the therapeutic response in a patient with metastatic lung adenocarcinoma using sequential study with ¹⁸F-FDG PET-CT and ¹⁸F-fluoride PET-CT].

    PubMed

    Moragas, M; Soler, M; Riera, E; García, J R

    2015-01-01

    We report a case of a patient with lung adenocarcinoma and bone and extraosseus metastases studied with (18)F-FDG PET-CT, (99m)Tc-HMDP and (18)F-fluoride PET-CT. It assesses the usefulness of (18)F-FDG PET-CT for initial staging of the disease and monitoring response to therapy. For the study of the sclerotic bone metastases it shows the superiority of 99mTc-HMDP bone scintigraphy and (18)F-fluoride PET-CT over (18)F-FDG PET-CT, and (18)F-fluoride PET-CT over bone scintigraphy. It also shows the usefulness of (18)F-fluoride PET-CT for monitoring the bone metastases.

  13. MO-G-17A-09: Quantitative Autoradiography of Biopsy Specimens Extracted Under PET/CT Guidance

    SciTech Connect

    Fanchon, L; Carlin, S; Schmidtlein, C; Humm, J; Yorke, E; Solomon, S; Deasy, J; Kirov, A; Burger, I

    2014-06-15

    Purpose: To develop a procedure for accurate determination of PET tracer concentration with high spatial accuracy in situ by performing Quantitative Autoradiography of Biopsy Specimens (QABS) extracted under PET/CT guidance. Methods: Autoradiography (ARG) standards were produced from a gel loaded with a known concentration of FDG biopsied with 18G and 20G biopsy needles. Specimens obtained with these needles are generally cylindrical: up to 18 mm in length and about 0.8 and 0.6 mm in diameter respectively. These standards, with similar shape and density as biopsy specimens were used to generate ARG calibration curves.Quantitative ARG was performed to measure the activity concentration in biopsy specimens extracted from ten patients. The biopsy sites were determined according to PET/CT's obtained in the operating room. Additional CT scans were acquired with the needles in place to confirm correct needle placements. The ARG images were aligned with the needle tip in the PET/CT images using the open source CERR software. The mean SUV calculated from the specimen activities (SUVarg) were compared to that from PET (SUVpet) at the needle locations. Results: Calibration curves show that the relation between ARG signal and activity concentration in those standards is linear for the investigated range (up to 150 kBq/ml). The correlation coefficient of SUVarg with SUVpet is 0.74. Discrepancies between SUVarg and SUVpet can be attributed to the small size of the biopsy specimens compared to PET resolution. Conclusion: The calibration procedure using surrogate biopsy specimens provided a method for quantifying the activity within the biopsy cores obtained under FDG-PET guidance. QABS allows mapping the activity concentration in such biopsy specimens with a resolution of about 1mm. QABS is a promising tool for verification of biopsy adequacy by comparing specimen activity to that expected from the PET image. A portion of this research was funded by a research grant from

  14. Primary Uterine Peripheral T-cell Lymphoma: A Case Report of MRI and 18F-FDG PET/CT Findings.

    PubMed

    Gong, Jing; Dong, Aisheng; Wang, Yang; Zhang, Xuefeng; Yang, Panpan; Wang, Li; Jing, Wei

    2016-04-01

    Primary uterine non-Hodgkin's lymphoma is extremely rare accounting for <1% of all extranodal non-Hodgkin's lymphomas. Imaging findings of primary uterine lymphoma have rarely been reported before. We present magnetic resonance imaging (MRI) and fluorine-18-fluorodeoxyglucose (F-FDG) positron emission tomography (PET)/CT findings in a patient with primary uterine peripheral T-cell lymphoma.A 27-year-old female presented with intermittent fever with neutropenia for 7 months. MRI showed an ill-defined mass involved both the uterine corpus and cervix, resulting in diffuse enlargement of the uterus. This mass showed inhomogeneous hypointensity on unenhanced T1-weighted images, hyperintensity on diffusion-weighted imaging, relative hypointensity compared to the surrounding myometrium on T2-weighted images and lower enhancement than the surrounding myometrium on enhanced T1-weighted images. FDG PET/CT showed intense FDG uptake in the thickened wall of the uterine corpus and cervix with SUVmax of 26.9. There were multiple hypermetabolic lymph nodes in the pelvis and retroperitoneum. Uterine curettage and CT-guided biopsy of the uterine mass revealed peripheral T-cell lymphoma. Bone marrow biopsy revealed no evidence of lymphomatous involvement. The imaging and pathologic findings were consistent with primary uterine lymphoma. After 3 circles of chemotherapy, follow-up enhanced MRI showed decreased thickness of the uterine wall.Despite its rarity, primary uterine non-Hodgkin's lymphoma should be taken into consideration when a uterine tumor shows large size, relative hypointesity on both T2-weighted images and enhanced T1-weighted images compared to the surrounding myometrium, and intense FDG uptake on PET/CT. MRI may be helpful for describing the relationship between the tumor and adjacent structures. FDG PET/CT may be useful for tumor detection and staging.