SPECT/CT and sentinel node lymphoscintigraphy
Abstract The use of single-photon emission computed tomography/computed tomography (SPECT/CT) for sentinel node (SN) detection has been evaluated in the majority of malignancies with predominantly superficial lymphatic drainage. In breast cancer and melanoma, important initial contributions of SPECT/CT were based on the anatomical localisation of SNs already visualised on planar images, the detection of additional SNs in aberrant basins, and the depiction of SNs in cases with no visualisation on planar images. However, more recently, the finding that SPECT/CT use is associated with a higher rate of SN detection, m...
Source: Clinical and Translational Imaging - November 26, 2014 Category: Radiology Source Type: research

SPECT/CT: yesterday, today, tomorrow
(Source: Clinical and Translational Imaging)
Source: Clinical and Translational Imaging - November 25, 2014 Category: Radiology Source Type: research

SPECT/CT technology
This article describes some of the physical and technical fundamentals of SPECT/CT and reviews established as well as experimental technical developments. It also introduces the aforementioned recent trends in the field of nuclear medicine imaging, such as specialized collimators, SPECT cameras for anatomical imaging (e.g. cerebral/cardiac imaging) and new detector technologies. (Source: Clinical and Translational Imaging)
Source: Clinical and Translational Imaging - October 31, 2014 Category: Radiology Source Type: research

Ventilation-perfusion (V/Q) lung scintigraphy: a long journey to a renewed position of prominence in diagnosing pulmonary embolism
Abstract The ventilation-perfusion (V/Q) lung scan has traveled a long, circuitous path since its introduction for the diagnosis of pulmonary embolism (PE) in the 1960s. Its initial credibility was damaged following the publication of the PIOPED study in 1990 and the emergence of computed tomographic pulmonary angiography (CTPA) in the mid-1990s. A considerable number of advances in both methodology and image interpretation have helped to restore the credibility of V/Q. There has also been considerable concern over the large radiation burden associated with CTPA. The issue of overdiagnosis and overtreatment of sma...
Source: Clinical and Translational Imaging - October 21, 2014 Category: Radiology Source Type: research

Multimodality molecular imaging of the lung
Abstract Lung diseases cause significant morbidity and mortality and lead to high healthcare utilization. However, few lung disease-specific biomarkers are available to accurately monitor disease activity for the purposes of clinical management or drug development. Advances in cross-modal imaging technologies, such as combined positron emission tomography (PET) and magnetic resonance (MR) imaging scanners and PET or single-photon emission computed tomography (SPECT) combined with computed tomography (CT), may aid in the development of noninvasive, molecular-based biomarkers for lung disease. However, the lungs pos...
Source: Clinical and Translational Imaging - October 15, 2014 Category: Radiology Source Type: research

SPET–CT in thyroid cancer: a systematic review
Abstract The purpose of this study was to systematically review the utility of single-photon emission tomography–computed tomography (SPET–CT) fusion imaging in the investigation of thyroid cancer. We performed a systematic search of the world literature on radionuclide SPET–CT imaging of thyroid cancer using the medical databases Medline (OVID) and PubMed. The following search terms were used to identify relevant studies: (a) thyroid, combined with (b) SPECT/CT or SPECT–CT or SPET/CT or SPET–CT. The electronic searches returned citations for 1,189 potentially eligible articles and 98...
Source: Clinical and Translational Imaging - October 15, 2014 Category: Radiology Source Type: research

Lung scintigraphy in the diagnosis of pulmonary embolism: pathophysiological and practical evidence
In conclusion, a Q scan without a V scan, when properly interpreted according to the prospective investigative study of acute pulmonary embolism diagnosis methodology (presence or absence of wedge-shaped perfusion defects) and combined with the formulation of a pre-test clinical probability, can be used in most patients with clinical suspicion of PE, reducing costs and radiation load, increasing the practicality of the examination, and providing diagnostic accuracy comparable to that of CT angiography. (Source: Clinical and Translational Imaging)
Source: Clinical and Translational Imaging - September 27, 2014 Category: Radiology Source Type: research

Lung pathology and imaging
(Source: Clinical and Translational Imaging)
Source: Clinical and Translational Imaging - September 23, 2014 Category: Radiology Source Type: research

Critical review of SPECT imaging in pulmonary embolism
Abstract Outcome studies have shown that pulmonary embolism can be safely excluded in patients with negative ventilation/perfusion (V/Q) single-photon emission computed tomography (SPECT). The effective radiation dose of V/Q SPECT is much less than with computed tomographic (CT) pulmonary angiography, which would make it preferable to CT angiography in many young female patients. The accuracy of V/Q SPECT, however, is difficult to assess, because most published investigations are limited by incorporation bias or partial verification bias, as well as other limitations in study design and reporting. Consequently, th...
Source: Clinical and Translational Imaging - September 19, 2014 Category: Radiology Source Type: research

Aerosolised radionuclides for functional imaging in COPD/asthma
Abstract Radiolabelled aerosols provide a versatile means of studying the pathophysiology of lung disease. If aerosols consisting of small particles are used, a qualitative image of the distribution of ventilation is obtained. Larger particles are deposited by inertial impaction, mainly in larger airways. This mechanism is related to changes in the direction and velocity of airflow rather than to ventilation and is therefore very sensitive to airway narrowing. Measurements of aerosol deposition can therefore identify very early changes in the airways in chronic obstructive pulmonary disease (COPD) and asthma. Aero...
Source: Clinical and Translational Imaging - September 16, 2014 Category: Radiology Source Type: research

MR imaging in pulmonary embolism: does it have a future?
(Source: Clinical and Translational Imaging)
Source: Clinical and Translational Imaging - September 16, 2014 Category: Radiology Source Type: research

Molecular imaging of the pulmonary circulation in health and disease
Abstract The pulmonary circulation, at the unique crossroads between the left and the right heart, is submitted to large physiologic hemodynamic variations and possesses numerous important metabolic functions mediated through its vast endothelial surface. There are many pathologic conditions that can directly or indirectly affect the pulmonary vasculature and modify its physiology and functions. Pulmonary hypertension, the end result of many of these affections, is unfortunately diagnosed too late in the disease process, meaning that there is a crying need for earlier diagnosis and surrogate markers of disease pro...
Source: Clinical and Translational Imaging - September 9, 2014 Category: Radiology Source Type: research

Opportunities for nanotheranosis in lung cancer and pulmonary metastasis
In conclusion, opportunities for nanoparticle-based theranosis in primary lung cancer and pulmonary metastasis are presented and discussed. (Source: Clinical and Translational Imaging)
Source: Clinical and Translational Imaging - August 27, 2014 Category: Radiology Source Type: research

Role of PET quantitation in the monitoring of cancer response to treatment: review of approaches and human clinical trials
Abstract Positron emission tomography (PET) measures of cancer metabolism and cellular proliferation are increasingly being studied as markers of cancer response to treatment, with the goal of using them as predictors of patient therapeutic outcomes—i.e., as surrogate outcome measures. The primary PET radiotracers so far used for monitoring response of cancer to treatment are 18F-fluorodeoxyglucose (FDG) for studying abnormal energy metabolism and 18F-fluorothymidine (FLT) for examining cell proliferation. Both FDG and FLT PET quantitation of cancer response to treatment have been found to correlate with pa...
Source: Clinical and Translational Imaging - August 1, 2014 Category: Radiology Source Type: research

The role of PET quantification in neurological imaging: FDG and amyloid imaging in dementia
Abstract Positron emission tomography (PET) with FDG or amyloid tracers is an important diagnostic tool, which also provides imaging biomarkers for patient selection in therapeutic trials in Alzheimer’s disease. PET is also a quantitative technique with the potential to measure disease severity and progression. Limitations in spatial resolution result in partial volume effects that can be minimized by correction algorithms and image reconstruction with resolution recovery. Quantitative local rates of cerebral glucose metabolism can be calculated from FDG uptake. Reaching the highest degree of accuracy still...
Source: Clinical and Translational Imaging - August 1, 2014 Category: Radiology Source Type: research

The role of dual and multiple time point imaging of FDG uptake in both normal and disease states
Abstract Dual time point imaging (DTPI) and delayed time point imaging have been used for the differentiation of inflammatory and malignant processes and found to enhance the specificity of FDG PET imaging for diagnostic and prognostic purposes. It has been shown that the degree of FDG uptake at the second acquisition time point after the baseline scan increases in malignant cells; in inflammatory or infectious disorders, on the other hand, FDG uptake decreases or remains unchanged at the second time point. Many groups have investigated the application of DTPI and its potential and limitations have been discussed...
Source: Clinical and Translational Imaging - August 1, 2014 Category: Radiology Source Type: research

The role of PET quantification in cardiovascular imaging
Abstract Positron emission tomography (PET) has several clinical applications in cardiovascular imaging. Myocardial perfusion imaging with PET allows accurate global and regional measurements of myocardial perfusion, myocardial blood flow and function at stress and rest in a single examination. Simultaneous assessment of function and perfusion by PET with quantitative software is currently routine practice. Combination of ejection fraction reserve with perfusion information may improve the identification of severe coronary artery disease. Myocardial viability can be estimated by quantitative comparison of fluorin...
Source: Clinical and Translational Imaging - August 1, 2014 Category: Radiology Source Type: research

The role of quantitative PET in predicting cancer treatment outcomes
Abstract Recent years have witnessed increasing use of positron emission tomography (PET) in cancer staging and monitoring. In particular, 18F-fluoro-2-deoxy-d-glucose (FDG) has frequently been used in clinical practice for tumor detection, staging, and gross tumor volume definition in different cancer sites. More recently, there has been accumulating evidence that pre- and intra-treatment FDG uptake could be used as a prognostic factor for predicting cancer treatment outcomes. Typically, quantitative analysis of FDG uptake is based on observed changes in the standardized uptake value (SUV). However, SUV descript...
Source: Clinical and Translational Imaging - August 1, 2014 Category: Radiology Source Type: research

The need for “objective measurements” in FDG and amyloid PET neuroimaging
Abstract The process leading to the identification and validation of biomarkers for the diagnosis of early Alzheimer’s disease (early AD) has been a major focus of research interest in the past 10 years, and has been accompanied by a debate on the feasibility of implementing the research criteria in clinical practice. In the context of imaging performed using the two currently identified classes of AD biomarkers, i.e. markers of pathology and neurodegeneration, amyloid PET and 18F-FDG PET imaging are decisive tools whose crucial value is acknowledged in the recent guidelines for the early diagnosis of ...
Source: Clinical and Translational Imaging - August 1, 2014 Category: Radiology Source Type: research

The need for quantitative PET in multicentre studies
(Source: Clinical and Translational Imaging)
Source: Clinical and Translational Imaging - August 1, 2014 Category: Radiology Source Type: research

PET quantification: strategies for partial volume correction
Abstract Despite the continuous evolution of positron emission tomography (PET) technology, the spatial resolution (SR) of PET images remains poor (4–6 mm) compared with that of computed tomography (CT) and magnetic resonance imaging (
Source: Clinical and Translational Imaging - June 1, 2014 Category: Radiology Source Type: research

Advanced kinetic modelling strategies: towards adoption in clinical PET imaging
Abstract Positron emission tomography (PET) is a highly quantitative imaging modality that can probe a number of functional and biological processes, depending on the radio-labelled tracer used. Static imaging, followed by analysis using semi-quantitative indices, such as the standardised uptake value, is used in the majority of clinical assessments in which PET has a role. However, considerably more information can be extracted from dynamic image acquisition protocols, followed by application of appropriate image reconstruction and tracer kinetic modelling techniques, but the latter approaches have mainly been r...
Source: Clinical and Translational Imaging - June 1, 2014 Category: Radiology Source Type: research

Deriving physiological information from PET images: from SUV to compartmental modelling
Abstract Positron emission tomography (PET) imaging has made it possible to detect the in vivo concentration of positron-emitting compounds accurately and non-invasively. In order to relate the radioactivity concentration measured using PET to the underlying physiological or biochemical processes, the application of mathematical models to describe tracer kinetics within a particular region of interest is necessary. Image analysis can be performed both by visual interpretation and quantitative assessment and, depending on the ultimate purposes of the analysis, several alternatives are available. In clinical practi...
Source: Clinical and Translational Imaging - June 1, 2014 Category: Radiology Source Type: research

Pathology-validated PET image data sets and their role in PET segmentation
Abstract Positron emission tomography (PET)/computed tomography has recently been finding broader application for the diagnosis, treatment and therapy assessment of malignant disease. Accurate definition of the tumor border is extremely important for the success of localized tumor therapies. PET promises to provide the metabolically active tumor volume and, at present, it is used for target definition in a variety of tumors. This process is, however, subject to uncertainties of different origin. Resolving these uncertainties is challenging, since validating PET images and segmentation contours against tumor patho...
Source: Clinical and Translational Imaging - June 1, 2014 Category: Radiology Source Type: research

A brief overview of novel approaches to FDG PET imaging and quantification
Abstract The widespread implementation of hybrid FDG PET/CT worldwide has brought about a paradigm shift in the use of diagnostic imaging—molecular imaging combining morphological and functional data is now at the forefront of patient management in many clinical settings, not only for initial diagnosis, staging, monitoring of response to treatment and detection of recurrence, but also for prognostication and disease characterization. Although developments have focused particularly on the qualitative visual analysis of images, FDG PET allows elaborate quantification, which should be explored much more in the...
Source: Clinical and Translational Imaging - June 1, 2014 Category: Radiology Source Type: research

Radiomics in PET: principles and applications
Abstract Radiomics is an evolving field in which the extraction of large amounts of features from diagnostic medical images may be used to predict underlying molecular and genetic characteristics, thereby improving treatment response prediction and prognostication and potentially allowing personalisation of cancer treatment. There is increasing interest in extracting additional data from PET images, particularly novel features that describe the heterogeneity of voxel intensities, but a number of potential limitations need to be recognised and overcome. Nevertheless, some early data suggest that extraction of addi...
Source: Clinical and Translational Imaging - June 1, 2014 Category: Radiology Source Type: research

Trends in PET quantification: opportunities and challenges
(Source: Clinical and Translational Imaging)
Source: Clinical and Translational Imaging - June 1, 2014 Category: Radiology Source Type: research