The development of a population of 4D pediatric XCAT phantoms for imaging research and optimization

Segars, W. Paul; Norris, Hannah; Sturgeon, Gregory M.; Zhang, Yakun; Bond, Jennifer; Minhas, Anum; Tward, Daniel J.; Ratnanather, J. Tilak; Miller, Michael I.; Frush, Donald P.; Samei, Ehsan

doi:10.1118/1.4926847

Cited by 55 publications

(45 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Simulations were, therefore, performed to validate these results for a patient population with higher lung shunts and to investigate the convergence of the iterative reconstruction algorithm for varying activity distributions, as these are known to affect the number of iterations required . For this the digital 4D XCAT anthropomorphic phantom was used, which provides an excellent model to answer questions regarding emission tomography studies that are hard to study otherwise …”

Section: Discussionmentioning

confidence: 99%

“…17 For this the digital 4D XCAT anthropomorphic phantom was used, which provides an excellent model to answer questions regarding emission tomography studies that are hard to study otherwise. 6,[18][19][20][21] In this study, the number of iterations was minimized as a means to reduce the calculation time of the Monte Carlobased OSEM algorithm while still guaranteeing a clinically acceptable accuracy in lung dose estimation. This approach is complementary to other means to decrease computation times, such as parallel computing, which all fit in the continuous efforts made to accelerate reconstruction algorithms.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Accuracy of SPECT/CT‐based lung dose calculation for Holmium‐166 hepatic radioembolization before OSEM convergence

et al. 2018

View full text Add to dashboard Cite

PurposeIn intra‐arterial hepatic radioembolization using Holmium‐166 (166Ho) microspheres, a predicted lung‐absorbed dose of more than 30 Gy is a contraindication for therapy. Therefore, scout imaging by means of quantitative SPECT of the lungs after a low‐dose pretreatment session is essential. Earlier we showed the superiority of Monte Carlo‐based iterative SPECT reconstructions over conventional reconstructions due to its quantitative nature, required for dosimetry, at the cost of substantial computation times. In clinical routine, however, the limited available time between scout imaging and therapy constrains its application. To reduce computation times, we investigated the minimum number of iterations required to guarantee a clinical acceptable accuracy in lung dose estimation using patient and phantom data.Methods 166Ho scout SPECT data (range: 222‐283 MBq) were used from 10 patients. SPECT images were Monte Carlo‐based OSEM reconstructed (effective iterations: 240). Additionally, the 4D XCAT anthropomorphic phantom was used to mimic studies with an injected scout activity of 250 MBq and with varying lung‐absorbed doses ranging from 0.9 to 225 Gy for a therapeutic dosage of 15 GBq. These studies were reconstructed in the same way as the patient data, and were also reconstructed using a clinically available, standard OSEM algorithm for comparison. Lung‐absorbed dose was determined using VOI analysis as a function of iterations.ResultsThe estimated lung‐absorbed dose in nine patients ranged upon MC‐based OSEM convergence from 0 to 0.26 Gy for a therapeutic dosage. One patient had an estimated lung absorbed‐dose for a therapeutic dosage of 20.3 Gy upon MC‐based OSEM convergence, or 18.4 Gy after 40 iterations (−9%). The phantom data showed that the lung‐absorbed dose upon OSEM convergence was underestimated by 15% as compared to the actual simulated lung dose, and the dose after 40 iterations was underestimated by 9% as compared to the dose upon convergence. Both underestimations were irrespective of the magnitude of the lung‐absorbed dose (0.9 to 225 Gy) and thus can be easily corrected for. The quantitative accuracy of the MC‐based OSEM reconstructions (40 iterations, before convergence) outperformed the clinical OSEM reconstruction while estimating the lung dose.ConclusionsThe number of effective iterations necessary for quantitative estimation of the lung dose using MC‐based OSEM can be reduced from 240 to 40. The resulting sixfold reduction in calculation time enables processing of the scout images before therapy administration.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Accuracy of SPECT/CT‐based lung dose calculation for Holmium‐166 hepatic radioembolization before OSEM convergence

et al. 2018

View full text Add to dashboard Cite

show abstract

“…The XCAT library of adult and pediatric phantoms was created in this manner. 18,19 Recent works have focused on deep learning algorithms for automatic multiorgan image segmentation. [20][21][22] If successful, such algorithms can replace the time-consuming manual methods previously used in the phantom development process.…”

Section: Whole Body Phantomsmentioning

confidence: 99%

Virtual clinical trials in medical imaging: a review

et al. 2020

View full text Add to dashboard Cite

The accelerating complexity and variety of medical imaging devices and methods have outpaced the ability to evaluate and optimize their design and clinical use. This is a significant and increasing challenge for both scientific investigations and clinical applications. Evaluations would ideally be done using clinical imaging trials. These experiments, however, are often not practical due to ethical limitations, expense, time requirements, or lack of ground truth. Virtual clinical trials (VCTs) (also known as in silico imaging trials or virtual imaging trials) offer an alternative means to efficiently evaluate medical imaging technologies virtually. They do so by simulating the patients, imaging systems, and interpreters. The field of VCTs has been constantly advanced over the past decades in multiple areas. We summarize the major developments and current status of the field of VCTs in medical imaging. We review the core components of a VCT: computational phantoms, simulators of different imaging modalities, and interpretation models. We also highlight some of the applications of VCTs across various imaging modalities.

show abstract

“…Using methods from computational anatomy, the XCAT male and female models have been expanded into a population of models representing the human body of varying ages, heights, and weights from newborn to adult 13–15 as shown in Fig. 3.…”

Section: Introductionmentioning

confidence: 99%

Application of the 4-D XCAT Phantoms in Biomedical Imaging and Beyond

Segars

Tsui

Cai

et al. 2018

IEEE Trans. Med. Imaging

View full text Add to dashboard Cite

The four dimensional (4D) eXtended CArdiac-Torso (XCAT) series of phantoms was developed to provide accurate computerized models of the human anatomy and physiology. The XCAT series encompasses a vast population of phantoms of varying ages from newborn to adult, each including parameterized models for the cardiac and respiratory motions. With great flexibility in the XCAT’s design, any number of body sizes, different anatomies, cardiac or respiratory motions or patterns, patient positions and orientations, and spatial resolutions can be simulated. As such, the XCAT phantoms are gaining a wide use in biomedical imaging research. There they can provide a virtual patient base from which to quantitatively evaluate and improve imaging instrumentation, data acquisition, techniques and image reconstruction and processing methods which can lead to improved image quality and more accurate clinical diagnoses. The phantoms have also found great use in radiation dosimetry, radiation therapy, medical device design, and even the security and defense industry. This review paper highlights some specific areas in which the XCAT phantoms have found use within biomedical imaging and other fields. From these examples, we illustrate the increasingly important role that computerized phantoms and computer simulation are playing in the research community.

show abstract

The development of a population of 4D pediatric XCAT phantoms for imaging research and optimization

Cited by 55 publications

References 31 publications

Accuracy of SPECT/CT‐based lung dose calculation for Holmium‐166 hepatic radioembolization before OSEM convergence

Accuracy of SPECT/CT‐based lung dose calculation for Holmium‐166 hepatic radioembolization before OSEM convergence

Virtual clinical trials in medical imaging: a review

Application of the 4-D XCAT Phantoms in Biomedical Imaging and Beyond

Contact Info

Product

Resources

About