Abstract:
:We give an overview of the role of Physics in Medicine and Biology in the development of tomographic reconstruction algorithms. We focus on imaging modalities involving ionizing radiation, CT, PET and SPECT, and cover a wide spectrum of reconstruction problems, starting with classical 2D tomography in the 1970s up to 4D and 5D problems involving dynamic imaging of moving organs.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Defrise M,Gullberg GTdoi
10.1088/0031-9155/51/13/R09subject
Has Abstractpub_date
2006-07-07 00:00:00pages
R139-54issue
13eissn
0031-9155issn
1361-6560pii
S0031-9155(06)01655-1journal_volume
51pub_type
杂志文章,评审abstract::In carbon-ion radiotherapy, single-beam delivery each day in alternate directions has been common practice for efficient operation, taking advantage of the Bragg peak and the relative biological effectiveness (RBE) for uniform dose conformation to a tumor. Treatments are usually fractionated and treatment plans are ev...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/1361-6560/62/3/1062
更新日期:2017-02-07 00:00:00
abstract::This study presents a theoretical approach to the dosimetry for small and non-equilibrium radiation fields. We applied the newly developed VMCBC algorithm to the dosimetry for megavoltage photon beams using Monte Carlo techniques. The approach assumes that a Monte Carlo simulated beam can be calibrated per incident pa...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/53/13/006
更新日期:2008-07-07 00:00:00
abstract::A single photon absorptiometry method to measure the arterial concentration of injected iodinated contrast agent was developed. A prototype absorptiometry unit was built which consists of either a square or circular cross section acrylic (polymethylmethacrylate) cuvette connected to an arterial catheter at one end and...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/37/9/002
更新日期:1992-09-01 00:00:00
abstract::A recent paper proposed a novel technique for determining the total body water (TBW) of patients suffering with abnormal hydration levels, using a resonant cavity perturbation method. Current techniques to measure TBW are limited by resolution and technical constraints. However, this new method involves measuring the ...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/49/9/013
更新日期:2004-05-07 00:00:00
abstract::Factors affecting the accuracy of the in vivo measurement of cutaneous pigments and blood oxygenation by reflectance spectrophotometry have been examined. It was found that stray light, the amounts of haemoglobin and melanin, and the level of blood oxygenation all contributed to the measured reflectance and had to be ...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/35/9/009
更新日期:1990-09-01 00:00:00
abstract::We present an automatic bi-objective parameter-tuning approach for inverse planning methods for high-dose-rate prostate brachytherapy, which aims to overcome the difficult and time-consuming manual parameter tuning that is currently required to obtain patient-specific high-quality treatment plans. We modelled treatmen...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/1361-6560/ab7362
更新日期:2020-04-02 00:00:00
abstract::Photoacoustic imaging - a hybrid biomedical imaging modality finding its way to clinical practices. Although the photoacoustic phenomenon was known more than a century back, only in the last two decades it has been widely researched and used for biomedical imaging applications. In this review we focus on the developme...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/1361-6560/abd669
更新日期:2020-12-23 00:00:00
abstract::A recently described, computer aided method of attenuation analysis has been applied to free-air chamber measurements of the attenuation by up to 30mm A1 of the exposure rate of a narrow beam of X-radiation excited at a thick W target in a Be window tube by constant potentials of 60, 80, 100, 120 and 140 kV. It has ...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/22/2/001
更新日期:1977-03-01 00:00:00
abstract::A technique is presented to allow a breathing pattern to be obtained from any multi-slice CT, cone-beam or other series of sequential chest x-ray image sets. The technique requires no extra signals to be recorded and does not need specific external or internal oscillating structures to be visible in the field of view....
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/54/16/003
更新日期:2009-08-21 00:00:00
abstract::A 4D ordered-subsets maximum a posteriori (OSMAP) algorithm for dynamic SPECT is described which uses a temporal prior that constrains each voxel's behaviour in time to conform to a compartmental model. No a priori limitations on kinetic parameters are applied; rather, the parameter estimates evolve as the algorithm i...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/46/5/315
更新日期:2001-05-01 00:00:00
abstract::In order (i) to evaluate the dose uncertainty of the mouthpiece in daily use during intensity-modulated radiotherapy of patients with head and neck cancer, and (ii) to present a system for in vivo dosimetry of the oral mucosa, we equipped the mouthpiece with alanine dosimeter probes for in vivo dosimetry. The aim was ...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/56/5/010
更新日期:2011-03-07 00:00:00
abstract::The dearth of information on the physical processes involved in the propagation of ultrasound in tissue and the growing need for such information are discussed. The physical nature of the ultrasonic diagnostic process in considered in terms of a wave phenomenon and the limitations and advantages of frequency spectral ...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/20/5/009
更新日期:1975-09-01 00:00:00
abstract::The first goal of this paper is to clarify the reference conditions for the reference dosimetry of clinical proton beams. A clear distinction is made between proton beam delivery systems which should be calibrated with a spread-out Bragg peak field and those that should be calibrated with a (pseudo-)monoenergetic prot...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/59/17/4961
更新日期:2014-09-07 00:00:00
abstract::Compact gamma cameras with a square-shaped monolithic scintillator crystal and an array of silicon photomultipliers (SiPMs) are actively being developed for applications in areas such as small animal imaging, cancer diagnostics and radiotracer guided surgery. Statistical methods of position reconstruction, which are p...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/1361-6560/aa6029
更新日期:2017-05-07 00:00:00
abstract::In addition to being a powerful clinical tool, Positron emission tomography (PET) is also used in small laboratory animal research to visualize and track certain molecular processes associated with diseases such as cancer, heart disease and neurological disorders in living small animal models of disease. However, dosi...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/58/1/169
更新日期:2013-01-07 00:00:00
abstract::In situ and in vivo treatment plan verification and beam monitoring as well as dose control during heavy-ion tumour therapy can be performed in principle by measurements of range distributions of beta(+)-emitting nuclei by means of PET techniques. For this purpose the performance of different types of positron camera ...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/41/2/006
更新日期:1996-02-01 00:00:00
abstract::Pulsed nuclear magnetic resonance imaging (NMRI) apparatus has developed very quickly. On the other hand, the development of apparatus for pulsed electron paramagnetic resonance imaging (EPRI) has been very slow. This fact is due to the extremely reduced relaxation times of the paramagnetic probes. EPR linewidths are ...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/44/6/409
更新日期:1999-06-01 00:00:00
abstract::In this paper, the influence of a dynamic variation in the ambient pressure on the subharmonic response of phospholipid-coated microbubbles was investigated. The ambient pressure in water was modulated by a 2.5 kHz acoustic wave with a peak amplitude of 15 kPa. We investigated the fundamental and subharmonic emissions...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/56/19/018
更新日期:2011-10-07 00:00:00
abstract::A Monte Carlo model of a novel electronic portal imaging device (EPID) has been developed using Geant4 and its performance for imaging and dosimetry applications in radiotherapy has been characterised. The EPID geometry is based on a physical prototype under ongoing investigation and comprises an array of plastic scin...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/59/22/6827
更新日期:2014-11-21 00:00:00
abstract::To achieve accurate and fast deformable image registration (DIR) for pulmonary CT, we proposed a Multi-scale DIR framework with unsupervised Joint training of Convolutional Neural Network (MJ-CNN). MJ-CNN contains three models at multi-scale levels for a coarse-to-fine DIR to avoid being trapped in a local minimum. It...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/1361-6560/ab5da0
更新日期:2020-01-13 00:00:00
abstract::Three-dimensional reconstruction of cardiac vasculature from angiographic C-arm CT (rotational angiography) data is a major challenge. Motion artefacts corrupt image quality, reducing usability for diagnosis and guidance. Many state-of-the-art approaches depend on retrospective ECG-gating of projection data for image ...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/58/11/3717
更新日期:2013-06-07 00:00:00
abstract::In carbon ion therapy treatment planning, the relative biological effectiveness (RBE) is accounted for by optimization of the RBE-weighted dose (biological dose). The RBE calculation methods currently applied clinically in carbon ion therapy are derived from the microdosimetric kinetic model (MKM) in Japan and the loc...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/1361-6560/aae8b4
更新日期:2018-11-12 00:00:00
abstract::The transverse magnetic field of an MRI-linac sweeps contaminant electrons away from the radiation beam. Films oriented perpendicular to the magnetic field and 5 cm from the radiation beam edge show a projection of the divergent beam, indicating that contaminant electrons spiral along magnetic field lines and deposit ...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/1361-6560/aaba8f
更新日期:2018-05-01 00:00:00
abstract::A phantom study was performed in full-field digital mammography to investigate the opportunity and the magnitude of a possible dose reduction that would leave the image quality above the accepted thresholds associated with some classical phantoms. This preliminary work is intended to lay the groundwork for a future cl...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/50/8/015
更新日期:2005-04-21 00:00:00
abstract::The purpose of this paper was to study the source model for a Monte Carlo simulation of electron beams from a medical linear accelerator. In a prior study, a non-divergent Gaussian source with a full-width at half-maximum (FWHM) of 0.15 cm was successful in predicting relative dose distributions for electron beams wit...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/54/1/007
更新日期:2009-01-07 00:00:00
abstract::A mathematical procedure, using Fourier deconvolution, is described whereby diffusion-free proximity functions can be obtained from cloud-chamber data. Such non-diffused distributions can be used to obtain further microdosimetric and nanodosimetric quantities hitherto not available from experiments, thus making the cl...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/33/11/004
更新日期:1988-11-01 00:00:00
abstract::Reference dosimetry of photon fields is a well-established subject and currently available protocols (such as the IAEA TRS-398 and AAPM TG-51) provide methods for converting the ionization chamber (IC) reading into dose to water, provided reference conditions of charged particle equilibrium (CPE) are fulfilled. But th...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/51/6/011
更新日期:2006-03-21 00:00:00
abstract::Charge-coupled devices (CCDs) coupled to scintillation crystals can be used for high-resolution imaging with x-rays and gamma rays. When the CCD images can be read out fast enough, the energy and interaction position of individual gamma quanta can be estimated by a real-time image analysis of the scintillation light f...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/52/8/N01
更新日期:2007-04-21 00:00:00
abstract::New definitions of the absorbed dose conversion factors Clambda and CE are proposed. The absorbed dose in water is given by the product of absorbed dose conversion factor, exposure calibration factor, ionisation chamber reading, cap displacement correction factor and perturbation correction factor. At exposure calibra...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/23/2/003
更新日期:1978-03-01 00:00:00
abstract::Elastography, which uses ultrasound to image the tissue strain that results from an applied displacement, can display tumours and heat-ablated tissue with high contrast. However, its application to liver in vivo may be problematic due to the presence of respiratory and cardiovascular sources of displacement. The aim o...
journal_title:Physics in medicine and biology
pub_type: 临床试验,杂志文章
doi:10.1088/0031-9155/49/18/001
更新日期:2004-09-21 00:00:00