Photon-Counting CT: Technology, Current and Potential Future Clinical Applications, and Overview of Approved Systems and Those in Various Stages of Research and Development

References

• 1. Flohr T, Ulzheimer S, Petersilka M, Schmidt B. Basic principles and clinical potential of photon-counting detector CT. Chin J Acad Radiol. 2020;3(1):19–34.
  Google Scholar
• 2. Almqvist H, Crotty D, Nyren S, et al. Initial clinical images from a second-generation prototype silicon-based photon-counting computed tomography system. Acad Radiol 2024;31(2):572–581.
  Medline Google Scholar
• 3. Lee CL, Hong KJ, Kim N, et al. Feasibility study of portable multi-energy computed tomography with photon-counting detector for preclinical and clinical applications. Sci Rep 2021;11(1):22731.
  Medline Google Scholar
• 4. Panta RK, Butler APH, Butler PH, et al. First human imaging with MARS photon-counting CT. In: 2018 IEEE Nuclear Science Symposium and Medical Imaging Conference Proceedings (NSS/MIC). Institute of Electrical and Electronics Engineers, 2018.
  Google Scholar
• 5. Dunning CAS, O’Connell J, Robinson SM, et al. Photon-counting computed tomography of lanthanide contrast agents with a high-flux 330-μm-pitch cadmium zinc telluride detector in a table-top system. J Med Imaging (Bellingham) 2020;7(3):033502.
  Medline Google Scholar
• 6. Si-Mohamed SA, Boccalini S, Villien M, et al. First experience with a whole-body spectral photon-counting CT clinical prototype. Invest Radiol 2023;58(7):459–471.
  Medline Google Scholar
• 7. Alvarez RE, Macovski A. Energy-selective reconstructions in X-ray computerized tomography. Phys Med Biol 1976;21(5):733–744.
  Medline Google Scholar
• 8. Willemink MJ, Persson M, Pourmorteza A, Pelc NJ, Fleischmann D. Photon-counting CT: technical principles and clinical prospects. Radiology 2018;289(2):293–312.
  Google Scholar
• 9. Leng S, Bruesewitz M, Tao S, et al. Photon-counting detector CT: system design and clinical applications of an emerging technology. RadioGraphics 2019;39(3):729–743.
  Google Scholar
• 10. Boccalini S, Si-Mohamed S. Spectral photon counting CT: not just a pimped-up new version of dual-energy CT. Diagn Interv Imaging 2023;104(2):51–52.
  Medline Google Scholar
• 11. Roessl E, Brendel B, Engel KJ, Schlomka JP, Thran A, Proksa R. Sensitivity of photon-counting based K-edge imaging in X-ray computed tomography. IEEE Trans Med Imaging 2011;30(9):1678–1690.
  Medline Google Scholar
• 12. McCollough CH, Rajendran K, Leng S, et al. The technical development of photon-counting detector CT. Eur Radiol 2023;33(8):5321–5330.
  Medline Google Scholar
• 13. Kappler S, Henning A, Kreisler B, Schoeck F, Stierstorfer K, Flohr T. Photon counting CT at elevated X-ray tube currents: contrast stability, image noise and multi-energy performance. In: Whiting BR, Hoeschen C, eds. Medical imaging 2014: physics of medical imaging. SPIE, 2014; 368–375.
  Google Scholar
• 14. Danielsson M, Persson M, Sjölin M. Photon-counting x-ray detectors for CT. Phys Med Biol 2021;66(3):03TR01.
  Medline Google Scholar
• 15. Cammin J, Xu J, Barber WC, Iwanczyk JS, Hartsough NE, Taguchi K. A cascaded model of spectral distortions due to spectral response effects and pulse pileup effects in a photon-counting x-ray detector for CT. Med Phys 2014;41(4):041905.
  Medline Google Scholar
• 16. Mergen V, Sartoretti T, Cundari G, et al. The importance of temporal resolution for ultra-high-resolution coronary angiography: evidence from photon-counting detector CT. Invest Radiol 2023;58(11):767–774.
  Medline Google Scholar
• 17. Flohr T, Schmidt B. Technical basics and clinical benefits of photon-counting CT. Invest Radiol 2023;58(7):441–450.
  Medline Google Scholar
• 18. Euler A, Higashigaito K, Mergen V, et al. High-pitch photon-counting detector computed tomography angiography of the aorta: intraindividual comparison to energy-integrating detector computed tomography at equal radiation dose. Invest Radiol 2022;57(2):115–121.
  Medline Google Scholar
• 19. Rajendran K, Petersilka M, Henning A, et al. First clinical photon-counting detector CT system: technical evaluation. Radiology 2022;303(1):130–138.
  Google Scholar
• 20. Feldle P, Grunz JP, Huflage H, et al. Influence of helical pitch and gantry rotation time on image quality and file size in ultrahigh-resolution photon-counting detector CT. Sci Rep 2024;14(1):9358.
  Medline Google Scholar
• 21. Park SJ, Park J, Kim D, et al. The first mobile photon-counting detector CT: the human images and technical performance study. Phys Med Biol 2023;68(9):095013.
  Google Scholar
• 22. Han K, Ryu CH, Lee CL, Han TH. Deep learning-based material decomposition of iodine and calcium in mobile photon counting detector CT. PLoS One 2024;19(7):e0306627.
  Medline Google Scholar
• 23. Wetzl M, Dietzel M, Ohlmeyer S, Uder M, Wenkel E. Spiral breast computed tomography with a photon-counting detector (SBCT): the future of breast imaging? Eur J Radiol 2022;157:110605.
  Medline Google Scholar
• 24. Fan T, Zhang Z, Yang M, Quan G, Lai X. Image-domain material decomposition and beam hardening correction for photon-counting CT. In: 2023 IEEE Nuclear Science Symposium, Medical Imaging Conference and International Symposium on Room-Temperature Semiconductor Detectors (NSS MIC RTSD). Institute of Electrical and Electronics Engineers, 2023.
  Google Scholar
• 25. Simard M, Panta RK, Bell ST, Butler APH, Bouchard H. Quantitative imaging performance of MARS spectral photon-counting CT for radiotherapy. Med Phys 2020;47(8):3423–3434.
  Medline Google Scholar
• 26. Douek PC, Boccalini S, Oei EHG, et al. Clinical applications of photon-counting CT: a review of pioneer studies and a glimpse into the future. Radiology 2023;309(1):e222432.
  Google Scholar
• 27. Zhan X, Zhang R, Niu X, et al. Comprehensive evaluations of a prototype full field-of-view photon counting CT system through phantom studies. Phys Med Biol 2023;68(17):175007.
  Google Scholar
• 28. Lee D, Zhan X, Tai WY, Zbijewski W, Taguchi K. Improving model-data mismatch for photon-counting detector model using global and local model parameters. Med Phys 2024;51(2):964–977.
  Medline Google Scholar
• 29. Lambert JW, Sun Y, Stillson C, et al. An intravascular tantalum oxide-based CT contrast agent: preclinical evaluation emulating overweight and obese patient size. Radiology 2018;289(1):103–110.
  Google Scholar
• 30. Si-Mohamed S, Cormode DP, Bar-Ness D, et al. Evaluation of spectral photon counting computed tomography K-edge imaging for determination of gold nanoparticle biodistribution in vivo. Nanoscale 2017;9(46):18246–18257.
  Medline Google Scholar
• 31. Fan T, Li X, Zhang Z, et al. Preliminary performance evaluation of a prototype whole body photon counting CT using moderate detector pixel size design. Presented at IEEE 2022, Milano, Italy, November 5–12, 2022.
  Google Scholar
• 32. Grönberg F, Yin Z, Maltz JS, Pelc NJ, Persson M. The effects of intra-detector Compton scatter on low-frequency DQE for photon-counting CT using edge-on-irradiated silicon detectors. Med Phys 2024;51(7):4948–4969.
  Medline Google Scholar
• 33. Holmes TW, Yin Z, Bujila R, et al. Ultrahigh-resolution K-edge imaging of coronary arteries with prototype deep-silicon photon-counting CT: initial results in phantoms. Radiology 2024;311(3):e231598.
  Google Scholar
• 34. Salyapongse AM, Rose SD, Pickhardt PJ, et al. Effect of patient positioning on CT number accuracy: a phantom study comparing energy integrating and deep silicon photon counting detector CT. J Comput Assist Tomogr 2025. 10.1097/RCT.0000000000001670. Published online January 6, 2025.
  Medline Google Scholar
• 35. Gallego Manzano L, Monnin P, Sayous Y, Becce F, Damet J, Viry A. Clinical commissioning of the first point-of-care spectral photon-counting CT for the upper extremities. Med Phys 2023;50(5):2844–2859.
  Medline Google Scholar
• 36. Lau LCM, Lee WYW, Butler APH, et al. Multi-energy spectral photon-counting computed tomography (MARS) for detection of arthroplasty implant failure. Sci Rep 2021;11(1):1554.
  Medline Google Scholar
• 37. Lowe C. MARS ultra-high-resolution imaging for improved characterisation of pre- and post-operative scaphoid fractures. figshare [preprint] https://doi.org/10.6084/m9.figshare.13541051.v1. Posted January 7, 2021. Accessed December 14, 2023.
  Google Scholar
• 38. Butler A. From the Higgs-boson to molecular radiology. Int J Mod Phys E 2021;30(08):2130004.
  Google Scholar
• 39. CMS Collaboration, Chatrchyan S, Khachatryan V, et al. Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC. Phys Lett B 2013;716(1):30–61.
  Google Scholar
• 40. Healy JL. Optimization of MARS scanners for material imaging of biological samples [dissertation] Christchurch, New Zealand: University of Canterbury, 2018. http://hdl.handle.net/10092/15946. Accessed June 18, 2024.
  Google Scholar
• 41. Li M, Niu C, Wang G, et al. Deep few-view high-resolution photon-counting extremity CT at halved dose for a clinical trial. arXiv 2403.12331 [preprint] https://arxiv.org/abs/2403.12331. March 19, 2024. Accessed August 15, 2024.
  Google Scholar
• 42. Moghiseh M, Clark JA, Amma MR, et al. MARS for molecular imaging and preclinical studies. In: Hsieh S, Iniewski K, eds. Photon counting computed tomography: clinical applications, image reconstruction and material discrimination. Springer, 2023; 63–92.
  Google Scholar
• 43. Moghiseh M, Searle E, Dixit D, et al. Spectral photon-counting CT imaging of gold nanoparticle labelled monocytes for detection of atherosclerosis: a preclinical study. Diagnostics (Basel) 2023;13(3):499.
  Medline Google Scholar
• 44. Kalender WA, Kolditz D, Steiding C, et al. Technical feasibility proof for high-resolution low-dose photon-counting CT of the breast. Eur Radiol 2017;27(3):1081–1086.
  Medline Google Scholar
• 45. Shim S, Kolditz D, Steiding C, et al. Radiation dose estimates based on Monte Carlo simulation for spiral breast computed tomography imaging in a large cohort of patients. Med Phys 2023;50(4):2417–2428.
  Medline Google Scholar
• 46. Berger N, Marcon M, Frauenfelder T, Boss A. Dedicated spiral breast computed tomography with a single photon-counting detector: initial results of the first 300 women. Invest Radiol 2020;55(2):68–72.
  Medline Google Scholar
• 47. Schmidt CS, Zellweger C, Wieler J, et al. Clinical assessment of image quality, usability and patient comfort in dedicated spiral breast computed tomography. Clin Imaging 2022;90:50–58.
  Medline Google Scholar
• 48. Rößler AC, Kalender W, Kolditz D, et al. Performance of photon-counting breast computed tomography, digital mammography, and digital breast tomosynthesis in evaluating breast specimens. Acad Radiol 2017;24(2):184–190.
  Medline Google Scholar
• 49. Ruth V, Kolditz D, Steiding C, Kalender WA. Investigation of spectral performance for single-scan contrast-enhanced breast CT using photon-counting technology: a phantom study. Med Phys 2020;47(7):2826–2837.
  Medline Google Scholar
• 50. Kranz PG, Amrhein TJ, Gray L. CSF venous fistulas in spontaneous intracranial hypotension: imaging characteristics on dynamic and CT myelography. AJR Am J Roentgenol 2017;209(6):1360–1366.
  Medline Google Scholar
• 51. Amrhein TJ, Gray L, Malinzak MD, Kranz PG. Respiratory phase affects the conspicuity of CSF-venous fistulas in spontaneous intracranial hypotension. AJNR Am J Neuroradiol 2020;41(9):1754–1756.
  Medline Google Scholar
• 52. Schwartz FR, Kranz PG, Malinzak MD, et al. Myelography using energy-integrating detector CT versus photon-counting detector CT for detection of CSF-venous fistulas in patients with spontaneous intracranial hypotension. AJR Am J Roentgenol 2024;222(4):e2330673.
  Medline Google Scholar
• 53. Madhavan AA, Yu L, Brinjikji W, et al. Utility of photon-counting detector CT myelography for the detection of CSF-venous fistulas. AJNR Am J Neuroradiol 2023;44(6):740–744.
  Medline Google Scholar
• 54. Schwartz FR, Malinzak MD, Amrhein TJ. Photon-counting computed tomography scan of a cerebrospinal fluid venous fistula. JAMA Neurol 2022;79(6):628–629.
  Medline Google Scholar
• 55. Prayer F, Kienast P, Strassl A, et al. Detection of post-COVID-19 lung abnormalities: photon-counting CT versus same-day energy-integrating detector CT. Radiology 2023;307(1):e222087.
  Google Scholar
• 56. Demehri S, Baffour FI, Klein JG, et al. Musculoskeletal CT imaging: state-of-the-art advancements and future directions. Radiology 2023;308(2):e230344.
  Google Scholar
• 57. Sonnow L, Salimova N, Behrendt L, et al. Photon-counting CT of elbow joint fractures: image quality in a simulated post-trauma setting with off-center positioning. Eur Radiol Exp 2023;7(1):15.
  Medline Google Scholar
• 58. Baffour FI, Rajendran K, Glazebrook KN, et al. Ultra-high-resolution imaging of the shoulder and pelvis using photon-counting-detector CT: a feasibility study in patients. Eur Radiol 2022;32(10):7079–7086.
  Medline Google Scholar
• 59. Zhou W, Huo D, Browne LP, Zhou X, Weinman J. Universal 120-kV dual-source ultra-high pitch protocol on the photon-counting CT system for pediatric abdomen of all sizes: a phantom investigation comparing with energy-integrating CT. Invest Radiol 2024;59(10):719–726.
  Medline Google Scholar
• 60. Pourmorteza A, Symons R, Reich DS, et al. Photon-counting CT of the brain: in vivo human results and image-quality assessment. AJNR Am J Neuroradiol 2017;38(12):2257–2263.
  Medline Google Scholar
• 61. Boccalini S, Si-Mohamed S, Dessouky R, Sigovan M, Boussel L, Douek P. Feasibility of human vascular imaging of the neck with a large field-of-view spectral photon-counting CT system. Diagn Interv Imaging 2021;102(5):329–332.
  Medline Google Scholar
• 62. Spampinato MV, Rodgers J, McGill LJ, Schoepf UJ, O’Doherty J. Image quality of photon-counting detector CT virtual monoenergetic and polyenergetic reconstructions for head and neck CT angiography. Clin Imaging 2024;108:110081.
  Medline Google Scholar
• 63. Scharm SC, Schaefer-Prokop C, Winther HB, et al. regional pulmonary morphology and function: photon-counting CT assessment. Radiology 2023;308(1):e230318.
  Google Scholar
• 64. Scharm SC, Vogel-Claussen J, Schaefer-Prokop C, et al. Quantification of dual-energy CT-derived functional parameters as potential imaging markers for progression of idiopathic pulmonary fibrosis. Eur Radiol 2021;31(9):6640–6651.
  Medline Google Scholar
• 65. Symons R, Pourmorteza A, Sandfort V, et al. Feasibility of dose-reduced chest CT with photon-counting detectors: initial results in humans. Radiology 2017;285(3):980–989.
  Google Scholar
• 66. Schwartz FR, Ria F, McCabe C, et al. Image quality of photon counting and energy integrating chest CT—prospective head-to-head comparison on same patients. Eur J Radiol 2023;166:111014.
  Medline Google Scholar
• 67. Sartoretti T, Landsmann A, Nakhostin D, et al. Quantum iterative reconstruction for abdominal photon-counting detector CT improves image quality. Radiology 2022;303(2):339–348.
  Google Scholar
• 68. Bette S, Decker JA, Braun FM, et al. Optimal conspicuity of liver metastases in virtual monochromatic imaging reconstructions on a novel photon-counting detector CT—effect of keV settings and BMI. Diagnostics (Basel) 2022;12(5):1231.
  Medline Google Scholar
• 69. McCollough CH, Rajendran K, Leng S. Standardization and quantitative imaging with photon-counting detector CT. Invest Radiol 2023;58(7):451–458.
  Medline Google Scholar
• 70. Baffour FI, Huber NR, Ferrero A, et al. Photon-counting detector CT with deep learning noise reduction to detect multiple myeloma. Radiology 2023;306(1):229–236.
  Google Scholar
• 71. Schwartz FR, Vinson EN, Spritzer CE, et al. prospective multireader evaluation of photon-counting CT for multiple myeloma screening. Radiol Imaging Cancer 2022;4(6):e220073.
  Google Scholar
• 72. Dodd JD, Leipsic JA. Evolving developments in cardiac CT. Radiology 2023;307(3):e222827.
  Google Scholar
• 73. Williams MC, Newby DE. Photon-counting CT: a step change leading to a revolution in coronary imaging. Radiology 2023;307(5):e231234.
  Google Scholar
• 74. Si-Mohamed SA, Boccalini S, Lacombe H, et al. Coronary CT angiography with photon-counting CT: first-in-human results. Radiology 2022;303(2):303–313.
  Google Scholar
• 75. Sandfort V, Bluemke DA. Overcoming a technological hurdle: coronary CT angiography with photon-counting CT. Radiology 2022;303(2):314–316.
  Google Scholar
• 76. Kwan AC, Pourmorteza A, Stutman D, Bluemke DA, Lima JAC. Next-generation hardware advances in CT: cardiac applications. Radiology 2021;298(1):3–17.
  Google Scholar
• 77. Hagar MT, Soschynski M, Saffar R, et al. Accuracy of ultrahigh-resolution photon-counting CT for detecting coronary artery disease in a high-risk population. Radiology 2023;307(5):e223305.
  Google Scholar
• 78. Dirrichs T, Tietz E, Rüffer A, et al. Photon-counting versus dual-source CT of congenital heart defects in neonates and infants: initial experience. Radiology 2023;307(5):e223088.
  Google Scholar
• 79. Hagen F, Hofmann J, Wrazidlo R, et al. Image quality and dose exposure of contrast-enhanced abdominal CT on a 1st generation clinical dual-source photon-counting detector CT in obese patients vs. a 2nd generation dual-source dual energy integrating detector CT. Eur J Radiol 2022;151:110325.
  Medline Google Scholar
• 80. Khanungwanitkul K, Schwartz FR. Photon-counting CT shows side-branch intraductal papillary mucinous neoplasm-pancreatic duct connection. Radiology 2024;312(2):e240611.
  Google Scholar
• 81. Leng S, Toia GV, Hoodeshenas S, et al. Standardizing technical parameters and terms for abdominopelvic photon-counting CT: laying the groundwork for innovation and evidence sharing. Abdom Radiol (NY) 2024;49(9):3261–3273.
  Medline Google Scholar
• 82. Sandfort V, Persson M, Pourmorteza A, Noël PB, Fleischmann D, Willemink MJ. Spectral photon-counting CT in cardiovascular imaging. J Cardiovasc Comput Tomogr 2021;15(3):218–225.
  Medline Google Scholar
• 83. Wolf EV, Halfmann MC, Varga-Szemes A, et al. Photon-counting detector CT virtual monoenergetic images for coronary artery stenosis quantification: phantom and in vivo evaluation. AJR Am J Roentgenol 2024;222(3):e2330481.
  Medline Google Scholar
• 84. Aquino GJ, O’Doherty J, Schoepf UJ, et al. Myocardial characterization with extracellular volume mapping with a first-generation photon-counting detector CT with MRI reference. Radiology 2023;307(2):e222030.
  Google Scholar
• 85. Kopp FK, Daerr H, Si-Mohamed S, et al. Evaluation of a preclinical photon-counting CT prototype for pulmonary imaging. Sci Rep 2018;8(1):17386.
  Medline Google Scholar
• 86. Boll DT, Patil NA, Paulson EK, et al. Focal cystic high-attenuation lesions: characterization in renal phantom by using photon-counting spectral CT—improved differentiation of lesion composition. Radiology 2010;254(1):270–276.
  Google Scholar
• 87. Pourmorteza A, Symons R, Sandfort V, et al. Abdominal imaging with contrast-enhanced photon-counting CT: first human experience. Radiology 2016;279(1):239–245.
  Google Scholar
• 88. Sartoretti T, Mergen V, Higashigaito K, Eberhard M, Alkadhi H, Euler A. Virtual noncontrast imaging of the liver using photon-counting detector computed tomography: a systematic phantom and patient study. Invest Radiol 2022;57(7):488–493.
  Medline Google Scholar
• 89. Lennartz S, Schoenbeck D, Kröger JR Jr, Borggrefe J, Henning Niehoff J. Photon-counting CT material decomposition: initial experience in assessing adrenal adenoma. Radiology 2023;306(1):202–204.
  Google Scholar
• 90. Pourmorteza A. Photon-counting CT to virtual noncontrast CT images. Radiology 2023;306(1):205–206.
  Google Scholar
• 91. Mergen V, Racine D, Jungblut L, et al. Virtual noncontrast abdominal imaging with photon-counting detector CT. Radiology 2022;305(1):107–115.
  Google Scholar
• 92. Sosna J. Photon-counting Detector CT: initial analysis of virtual noncontrast imaging. Radiology 2022;305(1):116–117.
  Google Scholar
• 93. Marcus RP, Fletcher JG, Ferrero A, et al. Detection and characterization of renal stones by using photon-counting-based CT. Radiology 2018;289(2):436–442.
  Google Scholar
• 94. Dobrolinska MM, van der Werf NR, van der Bie J, et al. Radiation dose optimization for photon-counting CT coronary artery calcium scoring for different patient sizes: a dynamic phantom study. Eur Radiol 2023;33(7):4668–4675.
  Medline Google Scholar
• 95. Racine D, Mergen V, Viry A, et al. Photon-counting detector CT with quantum iterative reconstruction: impact on liver lesion detection and radiation dose reduction. Invest Radiol 2023;58(4):245–252.
  Medline Google Scholar
• 96. Kijowski R, Fritz J. Emerging technology in musculoskeletal MRI and CT. Radiology 2023;306(1):6–19.
  Google Scholar
• 97. Koetzier LR, Mastrodicasa D, Szczykutowicz TP, et al. Deep learning image reconstruction for CT: technical principles and clinical prospects. Radiology 2023;306(3):e221257.
  Google Scholar
• 98. Marcus RP, Nagy DA, Feuerriegel GC, Anhaus J, Nanz D, Sutter R. Photon-counting detector CT with denoising for imaging of the osseous pelvis at low radiation doses: a phantom study. AJR Am J Roentgenol 2024;222(1):e2329765.
  Medline Google Scholar
• 99. Nowak T, Eberhard M, Schmidt B, et al. Bone mineral density quantification from localizer radiographs: accuracy and precision of energy-integrating detector CT and photon-counting detector CT. Radiology 2021;298(1):147–152.
  Google Scholar
• 100. Healy J, Searle E, Panta RK, et al. Ex-vivo atherosclerotic plaque characterization using spectral photon-counting CT: comparing material quantification to histology. Atherosclerosis 2023;378:117160.
  Medline Google Scholar
• 101. Mergen V, Sartoretti T, Baer-Beck M, et al. Ultra-high-resolution coronary CT angiography with photon-counting detector CT: feasibility and image characterization. Invest Radiol 2022;57(12):780–788.
  Medline Google Scholar
• 102. Halfmann MC, Bockius S, Emrich T, et al. Ultrahigh-spatial-resolution photon-counting detector CT angiography of coronary artery disease for stenosis assessment. Radiology 2024;310(2):e231956.
  Google Scholar
• 103. van Dam-Nolen DHK, Truijman MTB, van der Kolk AG, et al. Carotid plaque characteristics predict recurrent ischemic stroke and TIA: the PARISK (Plaque At RISK) study. JACC Cardiovasc Imaging 2022;15(10):1715–1726.
  Medline Google Scholar
• 104. Romero JM, Babiarz LS, Forero NP, et al. Arterial wall enhancement overlying carotid plaque on CT angiography correlates with symptoms in patients with high grade stenosis. Stroke 2009;40(5):1894–1896.
  Medline Google Scholar
• 105. Schindler A, Schinner R, Altaf N, et al. Prediction of stroke risk by detection of hemorrhage in carotid plaques: meta-analysis of individual patient data. JACC Cardiovasc Imaging 2020;13(2 Pt 1):395–406.
  Medline Google Scholar
• 106. Hao W, Xu Z, Lin H, Yan F. Using dual-source photon-counting detector CT to simultaneously quantify fat and iron content: a phantom study. Acad Radiol 2024;31(10):4119–4128.
  Medline Google Scholar
• 107. Lal BK, Khan AA, Kashyap VS, et al. Computed tomography angiographic biomarkers help identify vulnerable carotid artery plaque. J Vasc Surg 2022;75(4):1311–1322.e3.
  Medline Google Scholar
• 108. Paraskevas KI, Brown MM, Lal BK, et al. Recent advances and controversial issues in the optimal management of asymptomatic carotid stenosis. J Vasc Surg 2024;79(3):695–703.
  Medline Google Scholar
• 109. Yalon M, Inoue A, Thorne JE, et al. Infrapopliteal segments on lower-extremity CTA: prospective intraindividual comparison of energy-integrating detector CT and photon-counting detector CT. AJR Am J Roentgenol 2024;222(3):e2329778.
  Medline Google Scholar
• 110. Keser Z, Diehn FE, Lanzino G. Photon-counting detector CT angiography in cervical artery dissection. Stroke 2024;55(3):e48–e49.
  Medline Google Scholar
• 111. Madhavan AA, Bathla G, Benson JC, Diehn FE, Nagelschneider AA, Lehman VT. High yield clinical applications for photon counting CT in neurovascular imaging. Br J Radiol 2024;97(1157):894–901.
  Medline Google Scholar
• 112. Shaheen NH, Stroebel M, Welsh C, Gibney B, Hardie AD. Use of novel photon-counting detector CT for diagnosis of bowel infarction. Radiol Case Rep 2022;17(5):1674–1677.
  Medline Google Scholar
• 113. Suri HS, Li G, Gajic O. Epidemiology of acute respiratory failure and mechanical ventilation. In: Vincent JL, ed. Intensive care medicine. Springer, 2008; 193–202.
  Google Scholar
• 114. Benson JC, Rajendran K, Lane JI, et al. A new frontier in temporal bone imaging: photon-counting detector CT demonstrates superior visualization of critical anatomic structures at reduced radiation dose. AJNR Am J Neuroradiol 2022;43(4):579–584.
  Medline Google Scholar
• 115. Bette SJ, Braun FM, Haerting M, et al. Visualization of bone details in a novel photon-counting dual-source CT scanner—comparison with energy-integrating CT. Eur Radiol 2022;32(5):2930–2936.
  Medline Google Scholar
• 116. Wehrse E, Sawall S, Klein L, et al. Potential of ultra-high-resolution photon-counting CT of bone metastases: initial experiences in breast cancer patients. NPJ Breast Cancer 2021;7(1):3.
  Medline Google Scholar
• 117. Sawall S, Baader E, Wolf J, et al. Image quality of opportunistic breast examinations in photon-counting computed tomography: a phantom study. Phys Med 2024;122:103378.
  Medline Google Scholar
• 118. Alkadhi H, Euler A. The future of computed tomography: personalized, functional, and precise. Invest Radiol 2020;55(9):545–555.
  Medline Google Scholar
• 119. Pickhardt PJ, Summers RM, Garrett JW, et al. Opportunistic screening: Radiology scientific expert panel. Radiology 2023;307(5):e222044.
  Google Scholar
• 120. Pickhardt PJ, Graffy PM, Perez AA, Lubner MG, Elton DC, Summers RM. Opportunistic screening at abdominal CT: use of automated body composition biomarkers for added cardiometabolic value. RadioGraphics 2021;41(2):524–542.
  Google Scholar
• 121. Pickhardt PJ. Value-added opportunistic CT screening: state of the art. Radiology 2022;303(2):241–254.
  Google Scholar
• 122. Schwartz FR, Ashton J, Wildman-Tobriner B, et al. Liver fat quantification in photon counting CT in head to head comparison with clinical MRI—first experience. Eur J Radiol 2023;161:110734.
  Medline Google Scholar
• 123. Decker JA, Huber A, Senel F, et al. Anemia detection by hemoglobin quantification on contrast-enhanced photon-counting CT data sets. Radiology 2022;305(3):650–652.
  Google Scholar
• 124. Ding H, Klopfer MJ, Ducote JL, Masaki F, Molloi S. Breast tissue characterization with photon-counting spectral CT imaging: a postmortem breast study. Radiology 2014;272(3):731–738.
  Google Scholar
• 125. Pickhardt PJ, Pooler BD, Lauder T, del Rio AM, Bruce RJ, Binkley N. Opportunistic screening for osteoporosis using abdominal computed tomography scans obtained for other indications. Ann Intern Med 2013;158(8):588–595.
  Medline Google Scholar
• 126. Pickhardt PJ, Graffy PM, Zea R, et al. Automated abdominal CT imaging biomarkers for opportunistic prediction of future major osteoporotic fractures in asymptomatic adults. Radiology 2020;297(1):64–72.
  Google Scholar
• 127. Pickhardt PJ, Graffy PM, Zea R, et al. Automated CT biomarkers for opportunistic prediction of future cardiovascular events and mortality in an asymptomatic screening population: a retrospective cohort study. Lancet Digit Health 2020;2(4):e192–e200.
  Medline Google Scholar
• 128. Ren L, Rajendran K, McCollough CH, Yu L. Radiation dose efficiency of multi-energy photon-counting-detector CT for dual-contrast imaging. Phys Med Biol 2019;64(24):245003.
  Medline Google Scholar
• 129. Zhang W, Zhang S, Gao P, et al. The feasibility of NaGdF₄ nanoparticles as an x-ray fluorescence computed tomography imaging probe for the liver and lungs. Med Phys 2020;47(2):662–671.
  Medline Google Scholar
• 130. Feuerlein S, Roessl E, Proksa R, et al. Multienergy photon-counting K-edge imaging: potential for improved luminal depiction in vascular imaging. Radiology 2008;249(3):1010–1016.
  Google Scholar
• 131. Muenzel D, Bar-Ness D, Roessl E, et al. Spectral photon-counting CT: initial experience with dual-contrast agent K-edge colonography. Radiology 2017;283(3):723–728.
  Google Scholar
• 132. Lowe C. Cancer imaging using MARS spectral CT: new methods for detection. figshare [preprint] https://doi.org/10.6084/m9.figshare.13541924.v1. Posted January 7, 2021. Accessed December 14, 2023.
  Google Scholar
• 133. Cuccione E, Chhour P, Si-Mohamed S, et al. Multicolor spectral photon counting CT monitors and quantifies therapeutic cells and their encapsulating scaffold in a model of brain damage. Nanotheranostics 2020;4(3):129–141.
  Medline Google Scholar
• 134. Si-Mohamed SA, Sigovan M, Hsu JC, et al. In vivo molecular K-edge imaging of atherosclerotic plaque using photon-counting CT. Radiology 2021;300(1):98–107.
  Google Scholar
• 135. Sartoretti T, McDermott MC, Stammen L, et al. Tungsten-based contrast agent for photon-counting detector CT angiography in calcified coronaries: comparison to iodine in a cardiovascular phantom. Invest Radiol 2024;59(10):677–683.
  Medline Google Scholar
• 136. Roessler AC, Hupfer M, Kolditz D, Jost G, Pietsch H, Kalender WA. High atomic number contrast media offer potential for radiation dose reduction in contrast-enhanced computed tomography. Invest Radiol 2016;51(4):249–254.
  Medline Google Scholar
• 137. Yeh BM, FitzGerald PF, Edic PM, et al. Opportunities for new CT contrast agents to maximize the diagnostic potential of emerging spectral CT technologies. Adv Drug Deliv Rev 2017;113:201–222.
  Medline Google Scholar
• 138. Davidson B. Biological characteristics of cancers involving the serosal cavities. Crit Rev Oncog 2007;13(3):189–227.
  Medline Google Scholar
• 139. Loonis AT, Yu H, Glazer DI, Bay CP, Sodickson AD. Dual energy-derived metrics for differentiating adrenal adenomas from nonadenomas on single-phase contrast-enhanced CT. AJR Am J Roentgenol 2023;220(5):693–704.
  Medline Google Scholar