Virtual clinical trials (VCTs) require computer simulations of representative patients and images to evaluate compare changes in performance imaging technologies. The simulated are usually interpreted by model observers whose depends upon the selection cases used training evaluation models. This work proposes an efficient method simulate calibrate soft tissue lesions, which matches detectability threshold virtual human readings.Anthropomorphic breast phantoms were simulation four mass models...

Virtual clinical trials (VCTs) of medical imaging require realistic models human anatomy. For VCTs in breast imaging, a multi-scale Perlin noise method is proposed to simulate anatomical structures tissue the context an ongoing phantom development effort. Four distributions were used replace voxels representing compartments and Cooper's ligaments phantoms. Digital mammography tomosynthesis projections simulated using DBT system configuration. Power-spectrum analyses higher-order statistics...

In digital breast tomosynthesis (DBT), the reconstruction is calculated from x-ray projection images acquired over a small range of angles. One step in process to identify pixels that fall outside shadow breast, segment background (air). each projection, rays are back-projected these focal spot. All voxels along identified as air. By combining results all projections, outline can be determined for reconstruction. This paper quantifies accuracy this segmentation strategy DBT. study, physical...

A next generation tomosynthesis (NGT) system has been proposed to obtain higher spatial resolution than traditional digital breast (DBT) by achieving consistent sub-pixel resolution. Resolution and linear acquisition artifacts can be further improved creating multi-axis, x-ray tube paths. This requires synchronization of the generator, detector, motion controller for an path composed arbitrarily spaced projection points. We have implemented a state machine run on Arduino microcontroller that...

Our next-generation tomosynthesis (NGT) system prototype introduces additional geometric movements to conventional Digital Breast Tomosynthesis (DBT) acquisition geometries, provide isotropic super-resolution. These include x-ray source movement in the posteroanterior (PA) direction and detector z-direction (perpendicular breast support). The desired benefits of NGT are only achievable with precise calibration. In our previous work, a phantom 24 point-like ball bearings (BB's) at four...

We are developing a dedicated, combined breast positron emission tomography (PET)-tomosynthesis scanner. Both the PET and digital tomosynthesis (DBT) scanners integrated in single gantry to provide spatially co-registered 3D PET-tomosynthesis images. The DBT image will be used identify boundary density improve quantitative accuracy of image. This paper explores attenuation correction (AC) strategies that can performed with PET-DBT scanner obtain more accurate, high-resolution detector is...

Star pattern test objects are used to evaluate the high-contrast performance of imaging systems. These were investigate alternative scanning geometries for a prototype next-generation tomosynthesis (NGT) system. The NGT system has 2D planar source motion and linear detector motion, is capable myriad acquisition geometries. We designed virtual star with voxel size 5𝜇m, it spatial resolution three different Open Virtual Clinical Trials (OpenVCT) framework was simulate patterns Simulated x-ray...

In digital breast tomosynthesis (DBT), projection images are acquired as the x-ray tube rotates in plane of chest wall. We constructed a prototype next-generation (NGT) system that has an additional component motion perpendicular direction (

Computed super-resolution (SR) is a method of reconstructing images with pixels that are smaller than the detector element size; superior spatial resolution achieved through elimination aliasing and alteration sampling function imposed by reconstructed pixel aperture. By comparison, magnification mammography projection imaging uses geometric to increase resolution. This study explores development application digital breast tomosynthesis (MDBT). Four different acquisition geometries compared...

A method for geometric calibration of a next-generation tomosynthesis (NGT) system is proposed and tested. The NGT incorporates additional movements between projections over conventional DBT. These require precise to support magnification DBT isotropic SR. phantom was created project small tungsten-carbide ball bearings (BB's) onto the detector at four different magnifications. Using bandpass filter template matching, MATLAB program written identify centroid locations each BB projection on...

Digital breast tomosynthesis (DBT) systems utilize an isocentric acquisition geometry which introduces imaging artifacts that are deleterious to image reconstructions. The next-generation (NGT) prototype was designed incorporate various x-ray source and detector motions for the purpose of investigating alternative geometries DBT. Non-isocentric geometries, acquisitions vary magnification between projection images, capable ameliorating aliasing other intrinsic conventional We used virtual...

A spatial resolution metric is presented for tomosynthesis. The Fourier spectral distortion (FSD) was developed to evaluate specific properties of different imaging techniques digital tomosynthesis using a star pattern image plot modulation in the frequency domain. FSD samples star-pattern tangentially over an acute angle and range frequencies 2D or 3D reconstruction slice. graph portrays all present quadrant. In addition fundamental input pattern, shows leakage, square wave harmonics,...

A next generation tomosynthesis (NGT) prototype is under development to investigate alternative acquisition geometries for digital breast (DBT). positron emission tomography (PET) device will be integrated into the NGT facilitate DBT followed immediately by PET (PET-DBT). The aim of this study was identify custom that (1) improve dense/adipose tissue classification and (2) outline segmentation. Our lab's virtual clinical trial framework (OpenVCT) used simulate various acquisitions...

Our lab at the University of Pennsylvania (UPenn) is investigating novel designs for digital breast tomosynthesis. We built a next-generation tomosynthesis system with non-isocentric geometry (superior-to-inferior detector motion). This paper examines four metrics image quality affected by this design. First, aliasing was analyzed in reconstructions prepared smaller pixelation than detector. Aliasing assessed theoretical model r -factor, metric calculating amplitudes alias signal relative to...

Multiplanar reconstruction (MPR) in digital breast tomosynthesis (DBT) allows tomographic images to be portrayed various orientations. We have conducted research determine the resolution of MPR. built a phantom that houses star test pattern measure resolution. This provides three rotational degrees freedom. The design consists two hemispheres with longitudinal and latitudinal grooves reference angular increments. When joined together, form dome sits inside cylindrical encasement. encasement...

A next generation tomosynthesis (NGT) prototype has been developed to investigate alternative scanning geometries for digital breast (DBT). Performance of NGT acquisition is evaluated validate previous phantom experiments. Two custom were compared a conventional DBT geometry. Noise power spectra are used describe features specimen image reconstructions and compare geometries. improve high-frequency performance with superior isotropic super resolution, reduced out-of-plane blurring, better...

Tomosynthesis acquires projections over a limited angular range and thus samples an incomplete projection set of the object. For given acquisition geometry, extent tomosynthesis sampling can be measured in frequency domain based on Fourier Slice Theorem (FST). In this paper we propose term, "sampling comprehensiveness", to describe how comprehensively geometry domain, two measurements assess comprehensiveness: volume null space nearest sampled plane. Four geometries, conventional (linear),...

We are currently building a breast PET-Tomosynthesis scanner integrated in single gantry providing spatially co-registered 3D images. hypothesize the tomosynthesis can aid improving PET quantitation by attenuation correction (AC) based on identification of tissue-types present image. The detector consists 32 x array 1.5x1.5x15 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> LYSO crystals. utilizes two heads separated 9 cm, with each...

Digital breast tomosynthesis (DBT) reduces tissue overlap, which is a major limitation of digital mammography. However, DBT does not show significant improvement in calcification detection, because the limited angle and small number projections used to reconstruct 3D volume. Virtual clinical trials (VCTs) were evaluate benefits computed super resolution (SR) optimal combination acquisition parameters improve detection DBT. We simulated calcifications that embedded into software phantoms....

The impact of the angular range in conventional DBT is a trade-off image quality; increasing improves in-depth resolution and isotropic sampling across detector, but compromises in-plane resolution. Our next generation tomosynthesis (NGT) system capable two-dimensional source trajectory incorporates narrow- wide-angle acquisition orthogonal directions for single scan. In this work, performance NGT geometries high- low-frequency objects detector was evaluated via computer simulations. We...

A next generation tomosynthesis (NGT) system, capable of two-dimensional source motion, detector motion in the perpendicular direction, and magnification tomosynthesis, was constructed to investigate different acquisition geometries. Existing position-based geometric calibration methods proved ineffective when applied NGT

A next generation tomosynthesis (NGT) prototype was designed to investigate alternative scanning geometries for digital breast (DBT). The NGT system uses a 2D plane as an address space the x-ray source, and onedimensional linear detector motion determine acquisition geometry. This design provides myriad investigation. is also capable of magnification DBT. We performed image quality measurements evaluate performance both contact imaging in 3D. modulation transfer function (MTF) computed using...

The limited angle and number of projections in digital breast tomosynthesis (DBT) produce under-sampled datasets that may compromise calcification detection. Small lesions, such as microcalcifications, not be discernible without sufficient sampling the reconstructed DBT images. We propose a virtual clinical trial (VCT) method to evaluate detection using computer simulations phantoms, images, readers. used multiple-reader multiple-case (MRMC) receiver operating characteristic (ROC) analyses...

A multi-modality dedicated breast scanner which combines a high spatial resolution PET (BPET) and DBT has been developed. Phantom measurements demonstrate the BPET to have an in-plane of <2mm improved quantification sub-cm lesions in comparison with whole-body scanners. Measurements also suggest adequate count-rate capability support imaging scan time 2-5 mins. The will be useful for molecular features primary cancer provide intrinsically co-registered anatomic depicted by DBT. availability...