In recent years, statistical imaging reconstruction has been introduced in clinics by different computed tomography (CT) manufacturers as a means to reduce radiation dose levels. Essentially, the meth...
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Dual-energy computed tomography (CT) was first proposed in the 1970s but has wavered in practical usage ever since. In essence, the process employs two different X-ray spectra (i.e., a high energy lev...
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Phase contrast imaging exploits differences in the refractive index of materials to differentiate and image them. Recently, X-ray phase contrast imaging has attracted a great deal of attention. In the...
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With the advance of photon counting technology, spectral CT (multi-energy CT) has attracted lots of attention. The technique utilizes X-ray spectral information to identify and differentiate materials...
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Iterative image reconstruction techniques can be used to produce high quality tomographic images from noise-contaminated data. It is known that a statistical weight is critical for great image quality...
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With conventional image reconstruction, a single image is produced from a corresponding set of data. For example, an image can be reconstructed from a single CT sonogram or one MRI data set. Such dire...
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Assessing treatment response in cancer patients is essential to manage their disease and evaluate therapy. Computed tomography (CT) is widely used to monitor cancer treatment by measuring changes in t...
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The outcome of a stroke can hinge on the time spent on diagnosis and intervention. Perfusion imaging is a critical step in the process, wherein a patient is scanned to identify salvageable tissue. The...
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Visualizing a patient’s heart by non-invasive cardiovascular imaging is a powerful tool for diagnosis and therapy. Yet the heart’s movement and small branching arteries make quality cardiac imagin...
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Quantitative magnetic resonance imaging (qMRI) is a clinical procedure that can yield imaging biomarkers more sensitive and specific to underlying disease than regular MRI. It works by fitting images ...
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The introduction of 2-D detector arrays significantly improved the diagnostic potential of computed tomography (CT). However, accurate and efficient image construction from the data provided by these ...
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The X-ray source and radiation detector in a conventional computed tomography (CT) system are rotated on a gantry so that the angle at which the X-ray beams intersect the object constantly changes. In...
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In computed tomography (CT) imaging, divergent beam data acquisition modes have the potential to speed up data acquisition and shorten scan time. However, image reconstruction from divergent-beam proj...
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In clinical computed tomography (CT) practice, image artifacts arise when some data is missing or inconsistent, such as in the case of large patients that extend beyond the imaging field of view or pa...
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In a computed tomography (CT) system, an X-ray source projects a fan-shaped beam, which passes through the object being imaged and hits an array of radiation detectors. The source and detector array a...
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In a computed tomography (CT) system, an X-ray source projects a fan-shaped beam, which passes through the object being imaged and hits an array of radiation detectors. The source and detector array a...
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In imaging technologies, signal-to-noise ratio (SNR) is a quantitative measure of image quality. In medical imaging specifically, as SNR decreases, it becomes increasingly difficult to differentiate b...
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Most commercially available computed tomography (CT) systems employ image reconstruction methods based on the concepts of Radon space and the Radon transform. When a CT X-ray source projects a single ...
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Computed tomography (CT) uses special X-ray equipment to obtain image data from different angles of the body and generate a cross-sectional image of body tissues and organs. Because CT is a non-invasi...
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The Feldkamp (FDK) algorithm is widely used for image reconstruction for cone-beam projections, which are utilized in three-dimensional computed tomography (CT). However, because current FDK-type algo...
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One problem associated with intensity modulated radiation therapy (IMRT) is that the precise position, shape and size of the target often changes between the time the plan was developed and the actual...
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