Lung nodule localization and size estimation on chest tomosynthesis.

Purpose: We aim to investigate the localization, visibility, and measurement of lung nodules in digital chest tomosynthesis (DTS).

Approach: Computed tomography (CT), maximum intensity projections (CT-MIP) (transaxial versus coronal orientation), and computer-aided detection (CAD) were used as location reference, and inter- and intra-observer agreement regarding lung nodule size was assessed. Five radiologists analyzed DTS and CT images from 24 participants with lung , focusing on lung nodule localization, visibility, and measurement on DTS.

EVALUATION OF TWO CHEST TOMOSYNTHESIS CYSTIC FIBROSIS SCORING SYSTEMS USING HIGH-RESOLUTION COMPUTED TOMOGRAPHY BRODY SCORING AS REFERENCE.

Purpose: To evaluate two chest tomosynthesis (CTS) scoring systems for cystic fibrosis (CF), one system developed by Vult von Steyern et al. (VvS) and one system based on the Brody scoring system for high-resolution computed tomography (HRCT) (modified Brody (mB)). Brody scoring of HRCT was used as reference.

Detection of Pulmonary Nodule Growth with Chest Tomosynthesis: A Human Observer Study Using Simulated Nodules.

Rationale And Objectives: Chest tomosynthesis has been suggested as a suitable alternative to CT for follow-up of pulmonary nodules. The aim of the present study was to investigate the possibility of detecting pulmonary nodule growth using chest tomosynthesis.

Materials And Methods: Simulated nodules with volumes of approximately 100 mm and 300 mm as well as additional versions with increasing volumes were created.

Evaluation of a corrected implementation of a method of simulating pulmonary nodules in chest tomosynthesis.

Background A method of simulating pulmonary nodules in tomosynthesis images has previously been developed and evaluated. An unknown feature of a rounding function included in the computer code was later found to introduce an artifact, affecting simulated nodules in low-signal regions of the images. The computer code has now been corrected.

EFFECT OF RADIATION DOSE LEVEL ON ACCURACY AND PRECISION OF MANUAL SIZE MEASUREMENTS IN CHEST TOMOSYNTHESIS EVALUATED USING SIMULATED PULMONARY NODULES.

The aim of the present study was to investigate the dependency of the accuracy and precision of nodule diameter measurements on the radiation dose level in chest tomosynthesis. Artificial ellipsoid-shaped nodules with known dimensions were inserted in clinical chest tomosynthesis images. Noise was added to the images in order to simulate radiation dose levels corresponding to effective doses for a standard-sized patient of 0.

AN ANALYSIS OF THE POTENTIAL ROLE OF CHEST TOMOSYNTHESIS IN OPTIMISING IMAGING RESOURCES IN THORACIC RADIOLOGY.

The aim of the study was to investigate the potential role of chest tomosynthesis (CTS) at a tertiary referral centre by exploring to what extent CTS could substitute chest radiography (CXR) and computed tomography (CT). The study comprised 1433 CXR, 523 CT and 216 CTS examinations performed 5 years after the introduction of CTS. For each examination, it was decided if CTS would have been appropriate instead of CXR (CXR cases), if CTS could have replaced the performed CT (CT cases) or if CT would have been performed had CTS not been available (CTS cases).

VISIBILITY OF STRUCTURES OF RELEVANCE FOR PATIENTS WITH CYSTIC FIBROSIS IN CHEST TOMOSYNTHESIS: INFLUENCE OF ANATOMICAL LOCATION AND OBSERVER EXPERIENCE.

The aims of this study were to assess the visibility of pulmonary structures in patients with cystic fibrosis (CF) in digital tomosynthesis (DTS) using computed tomography (CT) as reference and to investigate the dependency on anatomical location and observer experience. Anatomical structures in predefined regions of CT images from 21 patients were identified. Three observers with different levels of experience rated the visibility of the structures in DTS by performing a head-to-head comparison with visibility in CT.

INFLUENCE OF THE IN-PLANE ARTEFACT IN CHEST TOMOSYNTHESIS ON PULMONARY NODULE SIZE MEASUREMENTS.

The aim of the present study was to investigate how the in-plane artefact present in the scan direction around structures in tomosynthesis images should be managed when measuring the size of nodules in chest tomosynthesis images in order to achieve acceptable measurement accuracy. Data from measurements, performed by radiologists, of the longest diameter of artificial nodules inserted in chest tomosynthesis images were used. The association between the measurement error and the direction of the longest nodule diameter, relative to the scan direction, was evaluated using the Kendall rank correlation coefficient.

IMAGE FUSION OF RECONSTRUCTED DIGITAL TOMOSYNTHESIS VOLUMES FROM A FRONTAL AND A LATERAL ACQUISITION.

Digital tomosynthesis (DTS) has been used in chest imaging as a low radiation dose alternative to computed tomography (CT). Traditional DTS shows limitations in the spatial resolution in the out-of-plane dimension. As a first indication of whether a dual-plane dual-view (DPDV) DTS data acquisition can yield a fair resolution in all three spatial dimensions, a manual registration between a frontal and a lateral image volume was performed.

THE APPLICATION OF IMPROVED, STRUCTURED AND INTERACTIVE GROUP LEARNING METHODS IN DIAGNOSTIC RADIOLOGY.

This study provides an example on how it is possible to design environments in a diagnostic radiology department that could meet learning demands implied by the introduction of new imaging technologies. The innovative aspect of the design does not result from the implementation of any specific tool for learning. Instead, advancement is achieved by a novel set-up of existing technologies and an interactive format that allows for focussed discussions between learners with different levels of expertise.

Image quality dependency on system configuration and tube voltage in chest tomosynthesis—a visual grading study using an anthropomorphic chest phantom.

Purpose: To investigate the potential benefit of increasing the dose per projection image in chest tomosynthesis, performed at the current standard dose level, by reducing the angular range covered or the projection image density and to evaluate the influence of the tube voltage on the image quality.

Methods: An anthropomorphic chest phantom was imaged using nine different projection image configurations and ten different tube voltages with the GE VolumeRAD tomosynthesis system. The resulting image sets were representative of being acquired at the same total effective dose.

Chest tomosynthesis: technical and clinical perspectives.

The recent implementation of chest tomosynthesis is built on the availability of large, dose-efficient, high-resolution flat panel detectors, which enable the acquisition of the necessary number of projection radiographs to allow reconstruction of section images of the chest within one breath hold. A chest tomosynthesis examination obtains the increased diagnostic information provided by volumetric imaging at a radiation dose comparable to that of conventional chest radiography. There is evidence that the sensitivity of chest tomosynthesis may be at least three times higher than for conventional chest radiography for detection of pulmonary nodules.

Evaluation of an improved method of simulating lung nodules in chest tomosynthesis.

Background: Simulated pathology is a valuable complement to clinical images in studies aiming at evaluating an imaging technique. In order for a study using simulated pathology to be valid, it is important that the simulated pathology in a realistic way reflect the characteristics of real pathology.

Purpose: To perform a thorough evaluation of a nodule simulation method for chest tomosynthesis, comparing the detection rate and appearance of the artificial nodules with those of real nodules in an observer performance experiment.

Rediscovering radiology: new technologies and remedial action at the worksite.

This study contributes to social studies of imaging and visualization practices within scientific and medical settings. The focus is on practices in radiology, which are bound up with visual records known as radiographs. The study addresses work following the introduction of a new imaging technology, tomosynthesis.

Evaluation of image quality and lesion perception by human readers on 3D CT colonography: comparison of standard and low radiation dose.

Aims: We compared the prevalence of noise-related artefacts and lesion perception on three-dimensional (3D) CT colonography (CTC) at standard and low radiation doses.

Methods: Forty-eight patients underwent CTC (64 x 0.625 mm collimation; tube rotation time 0.

Age and gender specific normal values of left ventricular mass, volume and function for gradient echo magnetic resonance imaging: a cross sectional study.

Background: Knowledge about age-specific normal values for left ventricular mass (LVM), end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV) and ejection fraction (EF) by cardiac magnetic resonance imaging (CMR) is of importance to differentiate between health and disease and to assess the severity of disease. The aims of the study were to determine age and gender specific normal reference values and to explore the normal physiological variation of these parameters from adolescence to late adulthood, in a cross sectional study.

Methods: Gradient echo CMR was performed at 1.

Physiological determinants of the variation in left ventricular mass from early adolescence to late adulthood in healthy subjects.

Background: The physiological determinants of left ventricular mass (LVM) measured by cardiac magnetic resonance (CMR) imaging are not well defined as prior investigators have studied either adults or adolescents in isolation or have not strictly excluded hypertension or accounted for the effects of exercise habits, haemodynamic, demographic, or body shape characteristics.

Methods: Ninety-seven healthy volunteers (11-81 years, 51 males) underwent CMR. All parameters [unstandardized and adjusted for body surface area (BSA)] were analysed according to gender and by adolescence versus adulthood (adolescents<20 years, adults>or=20 years).

Physiological determinants of the variation in left ventricular mass from early adolescence to late adulthood in healthy subjects.

Background: The physiological determinants of left ventricular mass (LVM) measured by cardiac magnetic resonance (CMR) imaging are not well defined as prior investigators have studied either adults or adolescents in isolation or have not strictly excluded hypertension or accounted for the effects of exercise habits, haemodynamic, demographic, or body shape characteristics.

Methods: A total of 102 healthy volunteers (12-81 years, 53 males) underwent CMR. All parameters [unstandardized and adjusted for body surface area (BSA)] were analysed according to gender and by adolescence versus adulthood (adolescents <20 years, adults > or = 20 years).

Nodule detection in digital chest radiography: effect of system noise.

Apart from the image content that is the reproduction of anatomy and possible lesions, an X-ray image also contains system noise due to the limited number of photons and other internal noise sources in the system (image plate artefacts, electronic noise, etc.). The aim of this study was to determine the extent to which the system noise influences the detection of subtle lung nodules in five different regions of the chest.