PURPOSE: In this study we evaluate the number of data partitions (gates) needed to sort 4D-PET and 4D-CT data to obtain motion-free images as a function of lesion size and motion displacement. METHODS: Plexiglas spheres of various diameters (8, 10, 15, 20, and 25 mm) were filled with a radioactive ...

Molecular imaging with positron emitting tomography (PET) is widely accepted as an essential part of the diagnosis and evaluation of neoplastic and non-neoplastic disease processes. PET has expanded its role from the research domain into clinical application for oncology, cardiology and neuropsychiatry. More recently, PET is being used as a ...

(11)C-methionine positron emission tomography ((11)C-methionine PET) provides accurate detection of brain tumors. Several reports have analyzed the correlation between uptake of (11)C-methionine and Ki-67 index or microvessel density non-stereotactically and suggested that (11)C-methionine uptake reflects both proliferation potential and angiogenic capability in gliomas. As gliomas possess heterogeneous histological architecture, non-stereotactic ...

Our aim is to investigate the impact of respiratory motion on tumor quantification and delineation in static PET/CT imaging using a population of patient respiratory traces. A total of 1295 respiratory traces acquired during whole body PET/CT imaging were classified into three types according to the qualitative shape of their ...

Respiration-correlated PET (RCPET) can reduce motion artifacts, but image quality generally decreases. The use of phase-by-phase attenuation correction (PAC) for RCPET using respiration-correlated CT (RCCT) requires large computational resources, and tumor positions will not always match correctly because of different binning methods for CT and PET. In this study, we ...

This study evaluated the causes of the frequently observed decreased myocardial perfusion in the lateral wall of the left ventricle in PET/CT studies with (13)N-ammonia in healthy adults. METHODS: Thirty-two adults who were undergoing PET/CT of the heart with (13)N-ammonia as part of a study of the effects of posttraumatic ...

Although 6-(18)F-fluoro-L-dopa ((18)F-FDOPA) has been available to study the striatal dopaminergic system for more than 2 decades, the full potential of the tracer was not realized before the introduction of (18)F-FDOPA PET and PET/CT to image a variety of neuroendocrine tumors (NETs) and pancreatic beta-cell hyperplasia. Together with receptor-based imaging, ...

In lung cancer, (18)F-FDG PET, CT, and (18)F-FDG PET/CT are used for noninvasive staging and therapy planning. Even with improved image registration techniques-especially in the modern hybrid PET/CT scanners-inaccuracies in the fusion process may occur, leading to errors in image interpretation. The aim of this study was to investigate by ...

We developed a maximum a posterior (MAP) reconstruction method for positron emission tomography (PET) image reconstruction incorporating magnetic resonance (MR) image information, with the joint entropy between the PET and MR image features serving as the regularization constraint. A non-parametric method was used to estimate the joint probability density of ...

We aimed to evaluate prospectively the efficacy of positron emission tomography (PET)/computed tomography (CT) plus brain magnetic resonance imaging (MRI) for detecting extrathoracic metastases in lung adenocarcinoma. Metastatic evaluations were feasible for 442 consecutive patients (M:F=238:204; mean age, 54 yr) with a lung adenocarcinoma who underwent PET/CT (CT, without IV ...

BACKGROUND: Positron emission tomography (PET)-computed tomography (CT) may be useful in the post-treatment follow-up of breast cancer patients. PURPOSE: To assess the usefulness of (18)F-fluorodeoxyglucose (FDG) PET-CT (PET-CT) for postoperative monitoring of breast cancer patients. MATERIAL AND METHODS: One hundred twenty-nine PET-CT studies performed on 55 female postoperative breast cancer ...

Imaging and measurement of proliferation with computed tomography (CT) and positron emission tomography (PET) provide a noninvasive method for improved staging and monitoring of response to cancer treatment. We evaluated prospectively the proliferation marker 3'-deoxy-3'[18F] fluorothymidine (FLT) in the context of FLT-PET/CT for detection of early response, confirmation of posttreatment ...

BACKGROUND: In 2005, 80% of cardiovascular disease (CVD) deaths occurred in low- to middle-income countries (i.e., developing nations). Cardiovascular imaging, such as myocardial perfusion SPECT, is one method that may be applied to detect and foster improved detection of at-risk patients. This document will review the availability and utilization for ...

PURPOSE: In detecting pheochromocytoma (PHEO), positron emission tomography (PET) with the radiolabelled amine precursor (18)F-fluorodihydroxyphenylalanine ((18)F-DOPA) offers excellent specificity, while computed tomography (CT) provides high sensitivity and ability to localize lesions; therefore, the combination of these modalities could be advantageous in this setting. The aim of this study was to ...

Many methods have been proposed for generating an image-derived input function (IDIF) exclusively from PET images. The purpose of this study was to assess the viability of a multimodality approach utilizing registered MR images. 3T-MR and HRRT-PET data were acquired from human subjects. Segmentation of both the left and right ...

The aim was to evaluate the diagnostic value of (18)F-fluorodeoxyglucose-positron emission tomography ((18)F-FDG PET), combined (18)F-fluorodeoxyglucose-positron emission tomography/computed tomography ((18)F-FDG PET/CT) and endoscopic ultrasonography (EUS) in diagnosing patients with pancreatic carcinoma. MEDLINE, EMBASE, Cochrane library and some other databases, from January 1966 to April 2009, were searched for initial studies. ...

Following the success of PET/CT during the last decade and the recent increasing proliferation of SPECT/CT, another hybrid imaging instrument has been gaining more and more interest: MR-PET. First combined, simultaneous PET and MR studies carried out in small animals demonstrated the feasibility of the new approach. Concurrently, some prototypes ...

PURPOSE: Optimal target delineation threshold values for positron emission tomography (PET) and computed tomography (CT) radiotherapy planning is controversial. In this present study, different PET CT threshold values were used for target delineation and then compared pathologically. METHODS AND MATERIALS: A total of 31 non-small-cell lung cancer patients underwent PET ...

PET imaging using [(18)F]fluorodeoxyglucose (FDG) and [(11)C]Pittsburgh compound B (PIB) have been proposed as biomarkers of Alzheimer disease (AD), as have CSF measures of the 42 amino acid beta-amyloid protein (Abeta(1-42)) and total and phosphorylated tau (t-tau and p-tau). Relationships between biomarkers and with disease severity are incompletely understood. Ten ...

The efficacy of systemically administered radiopharmaceuticals depends on the physiological path of the targeting molecule and the physical characteristics of the attached radionuclide. NM404 is a candidate for patient specific dosimetry because it can be used concurrently for both diagnosis and therapy. Radiolabeling NM404 with [(124)I] affords the possibility of ...

PURPOSE: The purpose of this study was to assess the influence of positron emission tomography-computed tomography (PET-CT) results on patient management from a single Canadian oncology center during its first 2 years of operation. METHODS: A total of 3,779 consecutive patients, 18 years of age and older, who were referred ...

PURPOSE: The added value of baseline positron emission tomography (PET) scans in therapy evaluation in malignant lymphoma is unclear. In guidelines, baseline PET is recommended but not mandatory except in lymphoma types with variable fluoro-D-glucose uptake. The aim of the present study was to test the hypothesis that adding baseline ...

OBJECTIVE: Erdheim-Chester disease (ECD) is a rare form of non-Langerhans' cell histiocytosis. The aim of this study was to assess the value of whole-body scanning with (18)F-fluorodeoxyglucose-positron emission tomography (FDG-PET) in a large cohort of ECD patients from a single center. METHODS: We retrospectively reviewed all PET scans performed on ...

To study the potential impact of iodine-124-beta-carbomethoxy-3beta(4-iodophenyl)tropane (I-124 betaCIT) in Parkinson disease, a I-124 betaCIT-PET scan was performed in 30-year-old man with suspected early Parkinson disease. The scan showed normal striatum uptake together with a focal spot in the left parietal cortex. The subsequent magnetic resonance imaging of the brain ...

AIM: Several studies consider 124I PET useful in the evaluation of differentiated thyroid cancer (DTC). The aim of this work was to evaluate the usefulness of 124I positron emission tomography (PET)/computed tomography (CT) for: 1) pretherapeutic staging; 2) optimizing the administering activity in case of remnants ablation; 3) individualizing a ...

PURPOSE: The need for an accurate lesion segmentation tool in 18FDG PET is a prerequisite for the estimation of lesion response to therapy, for radionuclide dosimetry, and for the application of 18FDG PET to radiotherapy planning. In this work, the authors have developed an iterative method based on a mathematical ...

Adult PET/CT acquisition protocols need to be modified for pediatric imaging to minimize the radiation dose while maintaining diagnostic utility. We developed pediatric PET/CT acquisition protocols customized to patient weight and estimated the dosimetry and cancer risk of these low-dose protocols to communicate basic imaging risks. METHODS: Protocols were developed ...

Field-cycled MRI (FCMRI) uses two independent, actively controlled resistive magnets to polarize a sample and to provide the magnetic field environment during data acquisition. This separation of tasks allows for novel forms of contrast, reduction of susceptibility artifacts, and a versatility in design that facilitates the integration of a second ...

The aim of this study was to iteratively develop and validate an (18)F-labeled small vascular cell adhesion molecule (VCAM)-1 affinity ligand and demonstrate the feasibility of imaging VCAM-1 expression by positron emission tomography-computed tomography (PET-CT) in murine atherosclerotic arteries. Hybrid PET-CT imaging allows simultaneous assessment of atherosclerotic lesion morphology (CT) ...

OBJECTIVE: A considerable change of urinary bladder (UB) shape in PET compared with CT in integrated PET/CT system is frequently noted. This study initially evaluated this finding with and without oral contrast (OC) use. In addition, a one bed pelvic section (PLV) repeat acquisition was investigated as a solution to ...

PURPOSE: Since meningiomas show a high expression of somatostatin receptor subtype 2, PET with (68)Ga-DOTATOC was proposed as an additional imaging modality beside CT and MRI for planning radiotherapy. We investigated the input of (68)Ga-DOTATOC-PET/CT on the definition of the "gross tumour volume" (GTV) in meningiomas, in order to assess ...

Positive interim positron emission tomography (PET) scans are thought to be associated with inferior outcomes in diffuse large B-cell lymphoma. In the E3404 diffuse large B-cell lymphoma study, PET scans at baseline and after 3 cycles of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone were centrally reviewed by a single reader. ...

BACKGROUND AND PURPOSE: To determine the consequences of target volume (TV) modifications, based on the additional use of PET information, on radiation planning, assuming PET/CT-imaging represents the true extent of the tumour. MATERIALS AND METHODS: For 21 patients with esophageal cancer, two separate TV's were retrospectively defined based on CT ...

This study was designed to compare tumor (18)F-FDG uptake between a single 20-s acquisition of deep-inspiration breath-hold PET/CT and free-breathing PET/CT for lung cancer. METHODS: Before the clinical study, a phantom study was performed to determine the optimum breath-hold time for the PET scan. We studied 47 patients with lung ...

BACKGROUND: 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) is a non-invasive whole-body imaging technique used to evaluate various types of malignancies. Recent advances have rapidly developed it into a diagnostic imaging tool in oncology. OBJECTIVES: In this study, the prevalence of thyroid incidentaloma and its cancer risk rate were investigated ...

Functional imaging plays a central role in the evaluation of some of the clinical problems faced by diabetic patients. In cardiovascular disease, myocardial perfusion imaging, particularly when complemented by gated SPECT, is a powerful tool not only for establishing the diagnosis of coronary artery disease, but also for providing prognostic ...

OBJECTIVE: To determine whether positron emission tomography/computed tomography (PET/CT) and indium In 111 pentetreotide, individually or collectively, predict the outcome of patients with neuroendocrine tumors (NETs). METHODS: Between July 31, 2002, and May 4, 2007, 29 patients with previously diagnosed NETs underwent both PET/CT and indium In 111 pentetreotide imaging ...

Multimodality imaging with positron emission tomography/computed tomography (PET/CT) and single-photon emission computed tomography (SPECT)/CT has become commonplace in clinical practice and in preclinical and basic biomedical research. Do other combinations of imaging modalities have a similar potential to impact medical science and clinical medicine? Presently, the combination of PET or ...

OBJECTIVE: Thorough evaluation of the musculoskeletal system on PET/CT requires a fund of specialized knowledge and the use of musculoskeletal-oriented viewing techniques. The study of musculoskeletal pitfalls introduces many subspecialty-specific topics and provides instruction in the methods necessary for optimal evaluation of the musculoskeletal system when interpreting PET/CT. CONCLUSION: This ...

In positron emission tomography, transmission scans can be performed to estimate attenuation correction factors (ACFs) which are in turn used to correct the emission scans. And such an attenuation correction is crucial for quantitatively accurate PET reconstructions. The prior model used in this work was based on our assumption that ...

Background: Positron emission tomography (PET)-computed tomography (CT) may be useful in the post-treatment follow-up of breast cancer patients. Purpose: To assess the usefulness of (18)F-fluorodeoxyglucose (FDG) PET-CT (PET-CT) for postoperative monitoring of breast cancer patients. Material and Methods: One hundred twenty-nine PET-CT studies performed on 55 female postoperative breast cancer ...

BACKGROUND: Airway inflammation plays a critical role in the progression of cystic fibrosis (CF) lung disease, and in the destruction of airways and lung parenchyma. Current methods to assess CF lung disease (BAL, spirometry, and high-resolution CT scanning), do not always accurately reflect actual disease states. Fluorodeoxyglucose (FDG)-PET scanning has ...

The use of PET/CT in children has grown substantially in the past few years. There is also an increased interest in keeping the radiation dose to children from CT as low as is clinically practical. This article reviews the physical aspects of both PET and CT separately and how CT ...

(68)Ga-labeled 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid-d-Phe(1)-Tyr(3)-octreotide (DOTA-TOC) PET has proven its usefulness in the diagnosis of patients with neuroendocrine tumors. Radionuclide therapy ((90)Y-DOTA-TOC or (177)Lu-DOTA-octreotate) is a choice of treatment that also requires an accurate diagnostic modality for early evaluation of treatment response. Our study compared (68)Ga-DOTA-TOC PET with CT or MRI using ...

The magnitude of the injected activity (A(0)) has a direct impact on the statistical quality of PET images. This study aimed to develop a generalized method for maximizing the statistical quality of dynamic PET images by optimizing A(0). METHODS: Patient-specific noise-equivalent counts (PS-NECs) were used as a metric of the ...

PURPOSE: A co-registered multimodality pattern analysis segmentation system (COMPASS) was developed to automatically delineate the radiation targets in head-and-neck cancer (HNC) using both (18)F-fluoro-deoxy glucose-positron emission tomography (PET) and computed tomography (CT) images. The performance of the COMPASS was compared with the results of existing threshold-based methods and radiation oncologist-drawn ...

PURPOSE: To find optimal threshold of length and GTV delineation for esophageal cancer using 18FDG PET/CT. MATERIALS AND METHODS: Sixteen patients with esophageal carcinoma underwent surgery. For each patient, six GTVs were defined. GTVCT was based on CT data alone. GTV20%, GTV40%, GTV2.5 and GTV40%M were generated by PET/CT, using ...

INTRODUCTION: Magnetic resonance imaging (MRI) is required for the investigation of surgically intractable epilepsy. In addition to the standard MRI techniques, perfusion sequences can be added to improve visualization of underlying pathological changes. Arterial spin-labeling (ASL) MRI perfusion does not require contrast administration and, for this reason, may have advantages ...

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) ...

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 ...