Rising analysis means that photon-counting computed tomography (PCCT) affords superior lung perfusion imaging than dual-energy CT at 52 p.c decrease radiation dosing.
For the research, not too long ago printed in European Radiology, researchers in contrast photon-counting detector computed tomography (PCD-CT) in 71 sufferers (imply age of 56.20) to dual-source, dual-energy CT (DECT) in a matched cohort (imply age of 55.95). For the DECT group, the researchers mentioned bronchopulmonary illness was the most typical indication for chest computed tomography angiography (CTA) (53.5 p.c) and pulmonary vascular illness was the most typical indication for CTA within the PCD-CT cohort (62 p.c).
The researchers discovered that PCD-CT had a decrease imply signal-to-noise ratio (SNR) (20.95 vs. 29.25) and a decrease imply contrast-to-noise ratio (CNR) compared to the DECT cohort (17.69 vs. 25.15). The research authors additionally mentioned the overwhelming majority of cardiogenic movement artifacts with the left ventricle have been gentle with PCD-CT (97.2 p.c) whereas reasonable artifacts have been reported in 73.2 p.c of those that had DECT.
The overwhelming majority of cardiogenic movement artifacts with the left ventricle have been gentle with PCD-CT (97.2 p.c) whereas reasonable artifacts have been reported in 73.2 p.c of those that had DECT, in line with a latest research. Right here one can see coronal views of lung perfusion (C) and lung imaging obtained with PCD-CT for a 19-year-old feminine. The imaging reveals beam-hardening artifacts in shut proximity to the appropriate of the mediastinum and an absence of cardiac movement artifacts close to the left ventricle. (Pictures courtesy of European Radiology.)
Sharp delineation of fissures was famous in 84.5 p.c of the scans for these within the PCD-CT cohort in distinction to 36.6 p.c of sufferers within the DECT group. Comparable enhancement of fissure delineation occurred with PCD-CT throughout variations in affected person weight, in line with the research authors.
“The numerous distinction within the scores of fissure visualization noticed within the general research group was additionally discovered when analyzing the inhabitants stratified by (physique mass index) BMI with a excessive proportion of fissures clearly recognized in 79.3% of chubby sufferers and 70.6% of overweight sufferers (vs. 25% and 27.8%, respectively (within the DECT group),” wrote lead research creator Martine Remy-Jardin, Ph.D., head of the Division of Thoracic Imaging on the College Hospital of Lille in Lille, France, and colleagues.
The researchers additionally discovered a considerably shorter imply CT acquisition time with PCD-CT (0.93 s vs. 3.98 s) and a 52 p.c discount within the imply quantity CT dose index (4.74 mGy vs. 9.07 mGy) compared to DECT. The research authors emphasised that key improvements and dose modulation capabilities improve the viability of PCD-CT in perfusion mapping.
Three Key Takeaways
1. Superior imaging high quality. Photon-counting computed tomography (PCCT) affords superior lung perfusion imaging in comparison with dual-energy CT (DECT), notably with sharper delineation of fissures and fewer cardiogenic movement artifacts.
2. Lowered radiation dose. The researchers famous that PCCT offered a 52 p.c decrease radiation dose than DECT, which is a big benefit in lowering affected person publicity to radiation throughout lung perfusion imaging.
3. Effectivity and Innovation: PCCT not solely shortens the imply CT acquisition time considerably (0.93 seconds vs. 3.98 seconds for DECT) but additionally incorporates key improvements and dose modulation capabilities that improve the viability and high quality of perfusion mapping.
“The calculation of high-quality perfusion maps on dual-source EID-CT is just attainable with diminished pitch values (to cut back spiral artifacts) and diminished complete collimation (to cut back the affect of cross-scattered radiation). … With PCD-CT, then again, technical improvements (spectral sensitivity of the detector, higher sampling within the longitudinal course of the affected person) make it attainable to work with wider complete collimation and the next pitch. The absence of dose modulation with EID-CT was a theoretical drawback because of a relentless radiation dose throughout acquisitions whereas dose modulation was a part of PCD-CT examinations,” identified Remy-Jardin and colleagues.
The researchers famous the CT scans have been obtained at 120 kVp with a 1.5 pitch worth however acknowledged the present availability of high-pitch acquisitions and that CT scans at 140 kVp provide higher spectral separation.
(Editor’s word: For associated content material, see “Research Says Photon-Counting CT Provides Higher Lung Evaluation than Standard CT,” “Research Reveals Advantages of Photon-Counting CT for Assessing Pulmonary Embolism” and “Might Digital Non-Distinction Pictures from Photon-Counting CT Scale back Radiation Dosing with CCTA?”)
In regard to check limitations, the authors conceded that using related injection protocols in each cohorts didn’t permit evaluation of lung perfusion with a decrease iodine load and pointed on the market was no comparability between the teams with respect to regional lung perfusion. The researchers famous the CT scans have been obtained at 120 kVp with a 1.5 pitch worth however acknowledged the present availability of high-pitch acquisitions and that CT scans at 140 kVp provide higher spectral separation.
