Article
Engineering, Biomedical
Kevin Treb, Jeff Radtke, Wesley S. Culberson, Ke Li
Summary: In photon counting detectors, the accumulation of electric pulses induced by multiple x-ray photons can lead to count losses. This study introduces an inexpensive readout circuit element to collect time-integrated charge to correct for pile-up-induced count losses. Experimental results demonstrate that this correction method can restore the count accuracy of paralyzable photon counting detectors, without impacting the spatial resolution of the images.
PHYSICS IN MEDICINE AND BIOLOGY
(2023)
Article
Computer Science, Interdisciplinary Applications
Xu Ji, Mang Feng, Kevin Treb, Ran Zhang, Sebastian Schafer, Ke Li
Summary: Modern interventional x-ray systems are often equipped with flat-panel detector-based cone-beam CT (FPD-CBCT) for high spatial resolution imaging. This study introduced a photon-counting detector (PCD) to C-arm systems as a supplementary option, providing high quality, spectral imaging capabilities. Experimental results showed that PCD-CT images had improved image quality and quantitative imaging capabilities compared to FPD-CBCT images at the same dose level.
IEEE TRANSACTIONS ON MEDICAL IMAGING
(2021)
Article
Radiology, Nuclear Medicine & Medical Imaging
Salim Si-Mohamed, Sara Boccalini, Pierre-Antoine Rodesch, Riham Dessouky, Elias Lahoud, Thomas Broussaud, Monica Sigovan, Delphine Gamondes, Philippe Coulon, Yoad Yagil, Loic Boussel, Philippe Douek
Summary: The study demonstrated that the large field-of-view SPCCT prototype has excellent technical capabilities and high image quality for high-resolution lung CT. Standard-dose SPCCT images had superior visibility and sharpness compared to conventional CT images, while low-dose SPCCT images showed similar clarity and visibility.
DIAGNOSTIC AND INTERVENTIONAL IMAGING
(2021)
Review
Radiology, Nuclear Medicine & Medical Imaging
Joachim E. E. Wildberger, Hatem Alkadhi
Summary: Noninvasive vascular imaging with CT has become essential in clinical practice, and the introduction of PCD-CT has further expanded its applications. Technical improvements of PCD-CT, including reduced noise levels, improved contrast-to-noise ratio, and full spectral multienergy data, have the potential to impact clinical decision making and patient outcomes. Early experience with PCD-CT technology has shown these improvements in various aspects. This review summarizes the advantages of PCD-CT for vascular imaging and discusses the PureLumen and PureCalcium algorithms.
INVESTIGATIVE RADIOLOGY
(2023)
Review
Radiology, Nuclear Medicine & Medical Imaging
Cynthia H. McCollough, Kishore Rajendran, Shuai Leng
Summary: Computed tomography (CT) images are highly quantitative and display anatomic structures in 3D. They are used for various applications, such as 3D printing of anatomical models and radiation therapy treatment planning. CT numbers, derived from pixel intensity, represent the x-ray attenuation coefficient and are widely used for quantitative measurements. However, the dependence of CT numbers on x-ray beam spectra limits their robust application. This article reviews the challenges faced by CT and introduces the benefits of photon-counting detector (PCD) CT technology, such as multienergy capability and improved spatial resolution.
INVESTIGATIVE RADIOLOGY
(2023)
Article
Instruments & Instrumentation
Rui Chen, Chao Cai, Wei Liu, Daoming Xi, Qingguo Xie
Summary: This paper introduces a multi-voltage threshold (MVT) digitizer using a time-varied threshold and explores its potential for developing a data acquisition system for photon-counting X-ray security inspection imaging. The digitizer compares scintillation pulses with a time-varied voltage signal and records the time information of intersections, allowing for the calculation of voltage values and extraction of energy information. Compared to traditional MVT digitizers, this method reduces complexity by requiring only one voltage comparator. Experimental results demonstrate that the proposed MVT digitizer is a promising approach for developing a YSO/SiPM-based photon-counting X-ray detector.
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
(2023)
Article
Engineering, Biomedical
Kevin Treb, York Haemisch, Christer Ullberg, Ran Zhang, Ke Li
Summary: This article presents a hybrid photon counting-energy integrating flat panel detector (FPD) design for upgrading interventional imaging. By replacing the central scintillator and thin-film transistor elements with a semiconductor photon counting detector (PCD) module, the imaging capabilities of the C-arm system can be improved while maintaining full field-of-view coverage. Experimental results show that this hybrid detector design can improve spatial resolution and contrast in vascular imaging, and provide seamless full field imaging. This design offers a cost-effective option for upgrading C-arm systems without compromising the clinical need for full field-of-view imaging.
PHYSICS IN MEDICINE AND BIOLOGY
(2023)
Article
Computer Science, Information Systems
Bingqing Xie, Yuemin Zhu, Pei Niu, Ting Su, Feng Yang, Lihui Wang, Pierre-Antoine Rodesch, Loic Boussel, Philippe Douek, Philippe Duvauchelle
Summary: Spectral photon-counting CT shows potential for quantitative material decomposition compared to traditional CT methods, but current challenges include accurate decomposition of low-concentration materials. This study proposes a super-energy-resolution method with coupled dictionary learning to improve material decomposition accuracy, showing significant progress in both physical phantoms and in vivo data.
Article
Engineering, Biomedical
Xu Ji, Kevin Treb, Ke Li
Summary: This work reports an experimentally observed edge enhancing effect in cadmium telluride-based photon counting detector systems. Through experimental measurements and theoretical modeling, it was found that the edge enhancing effect in the CS mode is related to pileup effects and negative correlations introduced by the CS circuit.
PHYSICS IN MEDICINE AND BIOLOGY
(2021)
Article
Computer Science, Interdisciplinary Applications
Lei Pan, Yihui He, Vladislav V. Klepov, Michael C. De Siena, Mercouri G. Kanatzidis
Summary: This study reports the performance of CsPbBr3 single-crystal semiconductor detectors capable of resolving the energies of single X-ray photons. By fine-tuning the working conditions, the detector demonstrates a high count rate for X-ray photon counting and exhibits low polarization over a typical timescale of multiple clinical X-ray scans. This demonstrates the potential of CsPbBr3 detectors for X-ray photon-counting applications in medical and industrial diagnostics, with lower cost compared to current state-of-the-art detectors.
IEEE TRANSACTIONS ON MEDICAL IMAGING
(2022)
Article
Engineering, Electrical & Electronic
Matti Kauppinen, Alex Winkler, Vili Lamsa, Mikko Matikkala, Miroslaw Zoladz, Pawel Grybos, Rafal Kleczek, Piotr Kmon, Robert Szczygiel, Tapio Fabritius
Summary: A seamless CdTe tile was developed for large-sized energy-selective X-ray detector panels, with a focus on spectral resolution and stability performance, along with the development of an automated pixel equalization method. The results suggest that the seamless tile is a feasible approach to scale up panel sizes, but further research is needed.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2021)
Article
Engineering, Biomedical
Kishore Rajendran, Martin Petersilka, Andre Henning, Elisabeth Shanblatt, Jeffrey Marsh, Jamison Thorne, Bernhard Schmidt, Thomas Flohr, Joel Fletcher, Cynthia McCollough, Shuai Leng
Summary: The study evaluated a full field-of-view photon-counting detector computed tomography system using phantoms and patient examples, showing excellent performance in image quality and potential clinical impact.
PHYSICS IN MEDICINE AND BIOLOGY
(2021)
Article
Engineering, Biomedical
Liang Li, Siyuan Zhang, Wenli Zhang, Hongbing Lu
Summary: This study upgraded the experimental XFCT system to achieve 3D XFCT images during one scan. A new scatter correction algorithm was proposed to estimate the scatter background and correct it using a weighted least squares method. The system showed potential for full-field in vivo XFCT imaging and was successfully used to study the distribution of GdNPs in mice.
PHYSICS IN MEDICINE AND BIOLOGY
(2023)
Article
Radiology, Nuclear Medicine & Medical Imaging
Qinghao Chen, Shuang Zhou, Yuewen Tan, Hao Yao, Zhongwei Zhang, Tom Mazur, Tiezhi Zhang
Summary: A tetrahedron beam X-ray system was developed with linear array X-ray source and detector, overcoming the scattering issue of traditional cone-beam systems, providing a larger field of view and lower scatter-to-primary ratio. The system can generate 2D and 3D X-ray images with image quality comparable to diagnostic helical CT.
Review
Medicine, General & Internal
Filippo Cademartiri, Antonella Meloni, Laura Pistoia, Giulia Degiorgi, Alberto Clemente, Carmelo De Gori, Vincenzo Positano, Simona Celi, Sergio Berti, Michele Emdin, Daniele Panetta, Luca Menichetti, Bruna Punzo, Carlo Cavaliere, Eduardo Bossone, Luca Saba, Riccardo Cau, Ludovico La Grutta, Erica Maffei
Summary: Photon-counting detector (PCD) is a novel computed tomography detector technology that has many advantages in the neurovascular field, such as increased spatial resolution, reduced radiation exposure, and optimization of contrast agents and material decomposition. This overview of literature on PCCT describes the principles, advantages, and disadvantages of conventional detectors and PCDs, and focuses specifically on its implementation in the neurovascular field.
JOURNAL OF CLINICAL MEDICINE
(2023)
