Computed tomography ct image reconstruction is an important technique used in a variety of domains, including medical imaging, electron microscopy, non. In tomophantom, the generated projection data are compatible with widelyused opensource tomographic reconstruction software. This new generation of image reconstruction software and hardware allows for a robust reduction of radiation dose in ct. Radiologists have been struggling to balance image noise with radiation dose in computed tomography ct scans for decades. Information from 15,000 ct examinations was collected, including all aspects of the exams such as scan parameter. December, 2011 siemens announced its computed tomography ct iterative reconstruction algorithm safire sinogram affirmed iterative reconstruction has been cleared for domestic sale by the u. In cbct reconstruction algorithms, iterative methods offer the potential to generate high quality images and would be an advantage especially for downsampling projection data. The basics for understanding what is iterative reconstruction. Implementation of iterative reconstruction offers the ability to minimize radiation exposure while preserving and, in some cases, improving image quality. However, in order to evaluate iterative reconstruction software, one must first understand the. Comparison of image noise in 56yearold obese man at standarddose ct.
Iterative reconstruction refers to iterative algorithms used to reconstruct 2d and 3d images in certain imaging techniques. However, computer speeds in the 1970s were so slow it took about 45. Modelbased iterative ct image reconstruction on gpus. A current limitation of iterative reconstruction, however, is the. When ct was developed by godfrey hounsfield in the 1970s, the original reconstruction algorithm he used was iterative reconstruction ir, where the software builds an image and then revises it with scores of reiterations to enhance image quality. Evaluation of 15,000 computed tomography ct examinations to investigate if iterative reconstruction ir reduces sustainably radiation exposure. Its focus is on iterative algorithms for improved image quality that have all been optimized to run on gpus including multigpus 1 for improved speed. The multiinstrument data analysis system midas tomography software originally designed for geophysical applications has been modified to cbct image reconstruction. Adaptive iterative reconstruction substantially reduces image quantum noise with no impact on spatial or contrast resolution. Reducing ct radiation dose with iterative reconstruction algorithms. Image quality is the main concern for reconstruction in comparison to conventional ct. Which is the best software for 3d reconstruction from ct.
The efficient multigpubased module for iterative ct reconstruction delivers superior image quality with comparably short reconstruction times. Cera ct reconstruction and artifact reduction siemens. Bouman a, sondre skatter b, mikhail kourinny b, and simon bedford c a purdue university, west lafayette, in, usa. I have used much software for 3d reconstruction and i have found that magics is the best tool for this work. Listing a study does not mean it has been evaluated by the u. The evolution of image reconstruction for ctfrom filtered.
Imr sets a new direction in ct image quality with industryleading lowcontrast resolution and virtually noisefree images. Except for precision learning, using conventional reconstruction methods with deep learning reconstruction prior is also an alternative approach to improve the image quality of deep learning reconstruction. To assess the dose performance in terms of image quality of filtered back projection fbp and two generations of iterative reconstruction ir algorithms developed by the most common ct vendors. Aidr 3d iterative reconstruction canon medical systems usa. At this lower patient dose level, if the greater image noise is modulated downward by adaptive statistical iterative reconstruction instead of using fbp, the lower. Adaptive statistical iterative reconstruction asir, a reconstruction engine that sweeps noise from ct images, allows radiologists to cut dose by up to 66% in abdominal scans with no change in spatial or temporal resolution, according to dr.
Which is the best software for 3d reconstruction from ct cbct. Aquilion ct through innovative design of hardware and software. Iterative reconstruction in ct and mri and a bit of pet and spect je. However, in order to evaluate iterative reconstruction software, one must first. The toolbox is now being extended for medical imaging application in iterative cbct and the results are verified against.
It is free software released under the gnu gplv2 intended for use in research and education. Iterative reconstruction in ct evolves for lower dose, increased clarity diagnostic imaging. However, it is not intuitive and as any open source software there is no. An interactive software was developed with the modeled 3d cat and the selected images using unity, version 5. High scan flexibility iterative reconstruction algorithms support virtually arbitrary ct scan trajectories. Ct images are created from data and a computer uses software to reconstruct this data into a diagnosticquality image. If you have problems with the reconstruction result from ct, if you are developing or modifying your ct system, and looking for adequate high quality ct reconstruction software, we can provide the best solution for you. The analytical reconstruction approaches, in general, try to formulate the solution in a. An improved statistical iterative algorithm for sparse. In recent years, iterative ct reconstruction method is drawing attention as a new ct reconstruction against backprojection ct reconstruction method.
Cone beam computed tomography cbct provides a volumetric image reconstruction from tomographic projection data. Impact of the depth of interaction in reconstruction of smallanimal spect data acquired with a spacevariable. For example, in computed tomography an image must be reconstructed from. Rather than increase scanner power and xray tube output to maximize signal, aquilion ct minimizes noise to allow for dose reduction.
Limited view angle iterative ct reconstruction sherman j. The reconstruction algorithm used is clearly important and should be carefully designed, developed and investigated before it can be applied clinically. Iterative reconstruction 101 imaging technology news. A current limitation of iterative reconstruction, however, is the long computing time. Does iterative reconstruction lower ct radiation dose. The toolbox is now being extended for medical imaging application in iterative cbct and the results are verified against commercial fdk results. While mbir is the most recent of the iterative reconstruction technologies, top manufacturers offer their own software answers to the noise versus dose argument. Although new to ct, iterative reconstruction is widely used in pet and was used when ct was introduced 5. Midas is a software package first developed as an image reconstruction software for ionospheric imaging technique 8. The purpose of this study was to compare the image noisereducing abilities of iterative model reconstruction imr with those of traditional filtered back projection fbp and statistical iterative reconstruction ir in abdominal computed tomography ct images.
Tigre is an opensource toolbox for fast and accurate 3d tomographic reconstruction for any geometry. Sinogramaffirmed iterative reconstruction of lowdose. Siemens safire iterative reconstruction protocol cleared. This was the underlying principle for the development of adaptive iterative dose reduction 3d aidr 3d. Iterative reconstruction ir processing of ct images the safety and scientific validity of this study is the responsibility of the study sponsor and investigators. It explains ct reconstruction features of ct reconstruction software. In contrast to idose 4, iterative model reconstruction aims at accounting for not only the noise behavior of the image but also the data statistics, image statistics. For quite some time, iterative reconstruction has been heavily discussed in the ct community as a highly promising method to achieve significant dose reduction without compromising image quality. The advantage of iterative ct reconstruction method is reconstruction results with high image quality can be obtained even with few projected imagesraw data.
Iterative reconstruction technique for reducing body. Iterative reconstruction is a reconstruction algorithm whereby image data are corrected with an assortment of models. But the competition just went up a notch or perhaps many notches with the recent fda approval of ge healthcares model based image reconstruction mbir technology, veo. The semiautomated reconstruction workflow requires no knowledge about iterative reconstruction to obtain best reconstruction results. Reducing ct radiation dose with iterative reconstruction. Iterative model reconstruction is the secondgeneration ir algorithm introduced by philips healthcare in 2012. Tomographic iterative gpubased reconstruction toolbox. Overall, the use of exact projections and known ground truth is especially beneficial for benchmarking of iterative reconstruction algorithms. Basics of iterative reconstruction methods in computed tomography. In this paper, we improve a statistical iterative algorithm based on the minimization of the image total variation tv for sparse or limited projection views during ct image reconstruction. Second, even if the software database is composed of several values of pitch, reconstruction thickness and reconstruction kernels, the results presented in.
Iterative reconstruction in ct evolves for lower dose. Shefer philips healthcare, cleveland, usa abstract computed tomography ct scanner technology has progressed rapidly throughout the past. New iterative cone beam ct reconstruction software. We put valuable information about the solution for your ct problems, so why not bookmark it. Recent studies with adaptive statistical iterative reconstruction, which combines a statistical form of iterative reconstruction with filtered back projectionreconstructed images, have reported the potential for a substantial decrease in radiation dose associated with chest and abdominal ct 9.
Ct image reconstruction tomoshop new generation ct. The efficient multigpubased module for iterative ct reconstruction. Advances in software and hardware have led to innovative algorithms and techniques that greatly reduce radiation and produce natural image impressions. View details of philips iterative model reconstruction.
Gpu petspect and ct reconstruction statistical iterative reconstruction research fields. This software was developed at the university of michigan by jeff fessler and his group. One of the main distinguishers of aquilion ct is its. Fbp tuning parameters challenging to characterize performance. The first ct scanners in the early 1970s already used iterative reconstruction algorithms. The aquilion ct design focuses on the second method. While mbir is the most recent of the iterative reconstruction technologies, top. Since then, this technique has caused a true hype in the field of radiology.
Recent advances in computing power have enabled the development of software based methods for iterative image reconstruction ir in ct. There fore, a modified and computationally faster iterative reconstruction technique, adaptive statistical iterative reconstruction, was devel. Innovations in hardware and the reconstruction algorithm result in a reconstruction speed less than three minutes for the majority of reference protocols that allows modelbased benefits to be achieved in even the most demanding applications. Although new to ct, iterative reconstruction is widely used in pet and was used when ct was introduced. Klink t1, obmann v2, heverhagen j3, stork a4, adam g5, begemann p6. Tomoshop new generation ct reconstruction software. Iterative reconstruction algorithms for computed tomography ct through total variation regularization based on piecewise constant assumption can produce accurate, robust, and stable results. Comparison of image quality from filtered back projection. Standard filtered back projection a and adaptive statistical iterative reconstruction asir b coronal multiplanar reformations from ct angiography at 2mm slice thickness show improved visualization of accessory left renal artery arrow on asir image. Image reconstruction techniques are used to create 2d and 3d images from sets of 1d projections. In fact, it took until 2009 for the first iterative reconstruction algorithms to come commercially available and replace conventional filtered back projection. Iterative reconstruction refers to an image reconstruction algorithm used in ct that begins with an image assumption, and compares it to real time measured values while making constant adjustments until the two are in agreement.
Another example is to build neural networks by unrolling iterative reconstruction algorithms. If nothing happens, download github desktop and try again. An adaptive shortcut which starts iterative reconstruction after a firstpass fbp reconstruction, adaptive statistical iterative reconstruction, can help shorten the longer reconstruction time of pure iterative reconstruction while maintaining much lower image noise than if the same raw data were reconstructed with fbp alone. These reconstruction techniques form the basis for common imaging modalities such as ct, mri, and pet, and they are useful in medicine, biology, earth science, archaeology, materials science, and nondestructive testing. Fast measurement times in industrial ct and lowdose dental ct imaging result in high noise levels in the projection images. Radiation exposure from multidetector computed tomography ct has become a pressing public health concern in both lay and medical publications. Which is the best software for 3d reconstruction from ct cbct images. Software that improves image quality is on track to be a champion of ct dose reduction now and in the future.
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