المؤلفون: Breiding, Philipe S, Gomollon, Ana Maria Turrion, Martini, Katharina, Nakhostin, Dominik, Alkadhi, Hatem, Euler, André

المصدر: Breiding, Philipe S; Gomollon, Ana Maria Turrion; Martini, Katharina; Nakhostin, Dominik; Alkadhi, Hatem; Euler, André (2024). Photon-Counting Detector CT for Kidney Stone Detection in Excretory Phase CT-Comparison Between Virtual Non-contrast and Virtual Non-iodine Reconstructions in a 3D Printed Kidney Phantom. Academic Radiology:Epub ahead of print.

مصطلحات موضوعية: Clinic for Diagnostic and Interventional Radiology, 610 Medicine & health

الوصف: RATIONALE AND OBJECTIVES To evaluate and compare the effectiveness of contrast media subtraction and kidney stone detection between a virtual non-iodine reconstruction algorithm (VNI; PureCalcium) and a virtual non-contrast (VNC) algorithm in excretory phase photon-counting detector computed tomography (PCD-CT), using a 3D printed kidney phantom under various tube voltages and radiation doses. MATERIALS AND METHODS A 3D-printed kidney phantom, holding Calcium Oxalate (CaOx) and uric acid stones within contrast-enhanced calyces, was created. The calyx density mirrored the average density observed in 200 excretory phase patients (916 HU at 110 kV). Imaging was conducted on a clinical dual-source PCD-CT at 120 kV and 140 kV, with radiation doses set at 5, 10, and 15 mGy. VNI and VNC algorithms were applied. Two blinded readers evaluated the image quality, along with the degree of contrast media and kidney stone subtraction, using visual scales. Krippendorff's alpha was calculated to determine inter-reader agreement, and the Chi-squared test was employed for comparing ordinal data. RESULTS Reader 2 rated overall image quality higher for VNI than VNC (4.90 vs. 4.00; P < .05), while Reader 1 found no significant difference (4.96 vs. 5.00; P > .05). Substantial agreement was observed between readers for contrast media subtraction in both VNC and VNI (Krippendorff's alpha range: 0.628-0.748). Incomplete contrast media subtraction occurred more frequently with VNI for both readers (Reader 1: 29% vs. 15%; P < .05; Reader 2: 24% vs. 20%; P > .05). Uric acid and smaller stones (<5 mm) were more likely to be subtracted than CaOx and larger stones in both VNC and VNI. Overall, a higher rate of stone subtraction was noted with VNI compared to VNC (Reader 1: 22% vs. 16%; Reader 2: 25% vs. 10%; P < .05). Neither radiation dose nor tube voltage significantly influenced stone subtraction (P > .05). CONCLUSION VNC demonstrated greater accuracy than VNI for contrast media subtraction and kidney stone visibility. ...

وصف الملف: application/pdf

العلاقة: https://www.zora.uzh.ch/id/eprint/259490/1/ZORA_259490.pdfTest; info:pmid/38641450; urn:issn:1076-6332

الإتاحة: https://doi.org/10.5167/uzh-259490Test
https://doi.org/10.1016/j.acra.2024.04.002Test
https://www.zora.uzh.ch/id/eprint/259490Test/
https://www.zora.uzh.ch/id/eprint/259490/1/ZORA_259490.pdfTest

المؤلفون: Racine, Damien, Mergen, Victor, Viry, Anaïs, Frauenfelder, Thomas, Alkadhi, Hatem, Vitzthum, Veronika, Euler, André

المصدر: Racine, Damien; Mergen, Victor; Viry, Anaïs; Frauenfelder, Thomas; Alkadhi, Hatem; Vitzthum, Veronika; Euler, André (2024). Photon-Counting Detector CT for Liver Lesion Detection-Optimal Virtual Monoenergetic Energy for Different Simulated Patient Sizes and Radiation Doses. Investigative Radiology:Epub ahead of print.

مصطلحات موضوعية: Clinic for Diagnostic and Interventional Radiology, 610 Medicine & health

الوصف: OBJECTIVES The aim of this study was to evaluate the optimal energy level of virtual monoenergetic images (VMIs) from photon-counting detector computed tomography (CT) for the detection of liver lesions as a function of phantom size and radiation dose. MATERIALS AND METHODS An anthropomorphic abdominal phantom with liver parenchyma and lesions was imaged on a dual-source photon-counting detector CT at 120 kVp. Five hypoattenuating lesions with a lesion-to-background contrast difference of -30 HU and -45 HU and 3 hyperattenuating lesions with +30 HU and +90 HU were used. The lesion diameter was 5-10 mm. Rings of fat-equivalent material were added to emulate medium- or large-sized patients. The medium size was imaged at a volume CT dose index of 5, 2.5, and 1.25 mGy and the large size at 5 and 2.5 mGy, respectively. Each setup was imaged 10 times. For each setup, VMIs from 40 to 80 keV at 5 keV increments were reconstructed with quantum iterative reconstruction at a strength level of 4 (QIR-4). Lesion detectability was measured as area under the receiver operating curve (AUC) using a channelized Hotelling model observer with 10 dense differences of Gaussian channels. RESULTS Overall, highest detectability was found at 65 and 70 keV for both hypoattenuating and hyperattenuating lesions in the medium and large phantom independent of radiation dose (AUC range, 0.91-1.0 for the medium and 0.94-0.99 for the large phantom, respectively). The lowest detectability was found at 40 keV irrespective of the radiation dose and phantom size (AUC range, 0.78-0.99). A more pronounced reduction in detectability was apparent at 40-50 keV as compared with 65-75 keV when radiation dose was decreased. At equal radiation dose, detection as a function of VMI energy differed stronger for the large size as compared with the medium-sized phantom (12% vs 6%). CONCLUSIONS Detectability of hypoattenuating and hyperattenuating liver lesions differed between VMI energies for different phantom sizes and radiation doses. Virtual monoenergetic ...

وصف الملف: application/pdf

العلاقة: https://www.zora.uzh.ch/id/eprint/253904/1/photon_counting_detector_ct_for_liver_lesion.189.pdfTest; info:pmid/38193782; urn:issn:0020-9996

الإتاحة: https://doi.org/10.5167/uzh-253904Test
https://doi.org/10.1097/RLI.0000000000001060Test
https://www.zora.uzh.ch/id/eprint/253904Test/
https://www.zora.uzh.ch/id/eprint/253904/1/photon_counting_detector_ct_for_liver_lesion.189.pdfTest

المؤلفون: Sartoretti, Thomas, Skawran, Stephan, Gennari, Antonio G., Maurer, Alexander, Euler, André, Treyer, Valerie, Sartoretti, Elisabeth, Waelti, Stephan, Schwyzer, Moritz, von Schulthess, Gustav K., Burger, Irene A., Huellner, Martin W., Messerli, Michael

المصدر: European Radiology, 34 (3)

مصطلحات موضوعية: Positron emission tomography, Noise, Algorithms, Dose reduction, Image enhancement

الوصف: Objectives: To introduce an automated computational algorithm that estimates the global noise level across the whole imaging volume of PET datasets. Methods: [18F]FDG PET images of 38 patients were reconstructed with simulated decreasing acquisition times (15–120 s) resulting in increasing noise levels, and with block sequential regularized expectation maximization with beta values of 450 and 600 (Q.Clear 450 and 600). One reader performed manual volume-of-interest (VOI) based noise measurements in liver and lung parenchyma and two readers graded subjective image quality as sufficient or insufficient. An automated computational noise measurement algorithm was developed and deployed on the whole imaging volume of each reconstruction, delivering a single value representing the global image noise (Global Noise Index, GNI). Manual noise measurement values and subjective image quality gradings were compared with the GNI. Results: Irrespective of the absolute noise values, there was no significant difference between the GNI and manual liver measurements in terms of the distribution of noise values (p = 0.84 for Q.Clear 450, and p = 0.51 for Q.Clear 600). The GNI showed a fair to moderately strong correlation with manual noise measurements in liver parenchyma (r = 0.6 in Q.Clear 450, r = 0.54 in Q.Clear 600, all p < 0.001), and a fair correlation with manual noise measurements in lung parenchyma (r = 0.52 in Q.Clear 450, r = 0.33 in Q.Clear 600, all p < 0.001). Classification performance of the GNI for subjective image quality was AUC 0.898 for Q.Clear 450 and 0.919 for Q.Clear 600. Conclusion: An algorithm provides an accurate and meaningful estimation of the global noise level encountered in clinical PET imaging datasets. Clinical relevance statement: An automated computational approach that measures the global noise level of PET imaging datasets may facilitate quality standardization and benchmarking of clinical PET imaging within and across institutions. Key Points: • Noise is an important quantitative marker ...

وصف الملف: application/application/pdf

العلاقة: http://hdl.handle.net/20.500.11850/661703Test

الإتاحة: https://doi.org/20.500.11850/661703Test
https://doi.org/10.3929/ethz-b-000661703Test
https://doi.org/10.1007/s00330-023-10056-wTest
https://hdl.handle.net/20.500.11850/661703Test

المؤلفون: Breiding, Philipe S., Gomollon, Ana Maria Turrion, Martini, Katharina, Nakhostin, Dominik, Alkadhi, Hatem, Euler, André

المصدر: Academic Radiology ; ISSN 1076-6332

مصطلحات موضوعية: Radiology, Nuclear Medicine and imaging

الإتاحة: https://doi.org/10.1016/j.acra.2024.04.002Test
https://api.elsevier.com/content/article/PII:S1076633224002095?httpAccept=text/xmlTest
https://api.elsevier.com/content/article/PII:S1076633224002095?httpAccept=text/plainTest

المؤلفون: Euler, André, Wullschleger, Sara, Sartoretti, Thomas, Müller, Daniel, Keller, Etienne Xavier, Lavrek, Dejan, Donati, Olivio

المصدر: Euler, André; Wullschleger, Sara; Sartoretti, Thomas; Müller, Daniel; Keller, Etienne Xavier; Lavrek, Dejan; Donati, Olivio (2023). Dual-energy CT kidney stone characterization-can diagnostic accuracy be achieved at low radiation dose? European Radiology, 33(9):6238-6244.

مصطلحات موضوعية: Urological Clinic, 610 Medicine & health

الوصف: OBJECTIVES To assess the accuracy of low-dose dual-energy computed tomography (DECT) to differentiate uric acid from non-uric acid kidney stones in two generations of dual-source DECT with stone composition analysis as the reference standard. METHODS Patients who received a low-dose unenhanced DECT for the detection or follow-up of urolithiasis and stone extraction with stone composition analysis between January 2020 and January 2022 were retrospectively included. Collected stones were characterized using X-ray diffraction. Size, volume, CT attenuation, and stone characterization were assessed using DECT post-processing software. Characterization as uric acid or non-uric acid stones was compared to stone composition analysis as the reference standard. Sensitivity, specificity, and accuracy of stone classification were computed. Dose length product (DLP) and effective dose served as radiation dose estimates. RESULTS A total of 227 stones in 203 patients were analyzed. Stone composition analysis identified 15 uric acid and 212 non-uric acid stones. Mean size and volume were 4.7 mm × 2.8 mm and 114 mm$^{3}$, respectively. CT attenuation of uric acid stones was significantly lower as compared to non-uric acid stones (p < 0.001). Two hundred twenty-five of 227 kidney stones were correctly classified by DECT. Pooled sensitivity, specificity, and accuracy were 1.0 (95%CI: 0.97, 1.00), 0.93 (95%CI: 0.68, 1.00), and 0.99 (95%CI: 0.97, 1.00), respectively. Eighty-two of 84 stones with a diameter of ≤ 3 mm were correctly classified. Mean DLP was 162 ± 57 mGy*cm and effective dose was 2.43 ± 0.86 mSv. CONCLUSIONS Low-dose dual-source DECT demonstrated high accuracy to discriminate uric acid from non-uric acid stones even at small stone sizes. KEY POINTS • Two hundred twenty-five of 227 stones were correctly classified as uric acid vs. non-uric acid stones by low-dose dual-energy CT with stone composition analysis as the reference standard. • Pooled sensitivity, specificity, and accuracy for stone characterization were ...

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العلاقة: https://www.zora.uzh.ch/id/eprint/239496/1/s00330_023_09569_1.pdfTest; info:pmid/36988716; urn:issn:0938-7994

الإتاحة: https://doi.org/10.5167/uzh-23949610.1007/s00330-023-09569-1Test
https://www.zora.uzh.ch/id/eprint/239496Test/
https://www.zora.uzh.ch/id/eprint/239496/1/s00330_023_09569_1.pdfTest

المؤلفون: Martini, Katharina, Jungblut, Lisa, Sartoretti, Thomas, Langhart, Sabinne, Yalynska, Tetyana, Nemeth, Bence, Frauenfelder, Thomas, Euler, André

المصدر: Martini, Katharina; Jungblut, Lisa; Sartoretti, Thomas; Langhart, Sabinne; Yalynska, Tetyana; Nemeth, Bence; Frauenfelder, Thomas; Euler, André (2023). Impact of radiation dose on the detection of interstitial lung changes and image quality in low-dose chest CT - Assessment in multiple dose levels from a single patient scan. European Journal of Radiology, 166:110981.

مصطلحات موضوعية: Clinic for Diagnostic and Interventional Radiology, 610 Medicine & health

الوصف: PURPOSE To assess image quality and detectability of interstitial lung changes using multiple radiation doses from the same chest CT scan of patients with suspected interstitial lung disease (ILD). METHOD Retrospective study of consecutive adult patients with suspected ILD receiving unenhanced chest CT as single-energy dual-source acquisition at 100 kVp (Dual-split mode). 67% and 33% of the overall tube current time product were assigned to tube A and B, respectively. 100%-dose was 2.34 ± 0.97 mGy. Five different radiation doses (100%, 67%, 45%, 39%, 33%) were reconstructed from this single acquisition using linear-blending technique. Two blinded radiologists assessed reticulations, ground-glass opacities (GGO) and honeycombing as well as subjective image noise. Percentage agreement (PA) as compared to 100%-dose were calculated. Non-parametric statistical tests were used. RESULTS A total of 228 patients were included (61.2 ± 14.6 years,146 female). PA was highest for honeycombing (>96%) and independent of dose reduction (P > 0.8). PA for reticulations and GGO decreased when reducing the radiation dose from 100% to 67% for both readers (reticulations: 83.3% and 93.9%; GGO: 87.7% and 79.8% for reader 1 and 2, respectively). Additional dose reduction did not significantly change PA for both readers (all P > 0.05). Subjective image noise increased with decreasing radiation dose (Spearman Rho of ρ = 0.34 and ρ = 0.53 for reader 1 and 2, respectively, P < 0.001). CONCLUSIONS Radiation dose reduction had a stronger impact on subtle interstitial lung changes. Detectability decreased with initial dose reduction indicating that a minimum dose is needed to maintain diagnostic accuracy in chest CT for suspected ILD.

وصف الملف: application/pdf

العلاقة: https://www.zora.uzh.ch/id/eprint/235144/1/ZORA235144.pdfTest; info:pmid/37478655; urn:issn:0720-048X

الإتاحة: https://doi.org/10.5167/uzh-23514410.1016/j.ejrad.2023.110981Test
https://www.zora.uzh.ch/id/eprint/235144Test/
https://www.zora.uzh.ch/id/eprint/235144/1/ZORA235144.pdfTest

المؤلفون: Turrion Gomollon, Ana Maria, Mergen, Victor, Sartoretti, Thomas, Polacin, Malgorzata, Nakhostin, Dominik, Puippe, Gilbert, Alkadhi, Hatem, Euler, André

المصدر: Turrion Gomollon, Ana Maria; Mergen, Victor; Sartoretti, Thomas; Polacin, Malgorzata; Nakhostin, Dominik; Puippe, Gilbert; Alkadhi, Hatem; Euler, André (2023). Photon-Counting Detector CT Angiography for Endoleak Detection After Endovascular Aortic Repair: Triphasic CT With True Noncontrast Versus Biphasic CT With Virtual Noniodine Imaging. Investigative Radiology, 58(11):816-821.

مصطلحات موضوعية: Clinic for Diagnostic and Interventional Radiology, 610 Medicine & health

الوصف: OBJECTIVES: The aim of this study was to compare image quality and endoleak detection after endovascular abdominal aortic aneurysm repair between a triphasic computed tomography (CT) with true noncontrast (TNC) and a biphasic CT with virtual noniodine (VNI) images on photon-counting detector CT (PCD-CT). MATERIALS AND METHODS: Adult patients after endovascular abdominal aortic aneurysm repair who received a triphasic examination (TNC, arterial, venous phase) on a PCD-CT between August 2021 and July 2022 were retrospectively included. Endoleak detection was evaluated by 2 blinded radiologists on 2 different readout sets (triphasic CT with TNC-arterial-venous vs biphasic CT with VNI-arterial-venous). Virtual noniodine images were reconstructed from the venous phase. The radiologic report with additional confirmation by an expert reader served as reference standard for endoleak presence. Sensitivity, specificity, and interreader agreement (Krippendorf α) were calculated. Image noise was assessed subjectively in patients using a 5-point scale and objectively calculating the noise power spectrum in a phantom. RESULTS: One hundred ten patients (7 women; age, 76 ± 8 years) with 41 endoleaks were included. Endoleak detection was comparable between both readout sets with a sensitivity and specificity of 0.95/0.84 (TNC) versus 0.95/0.86 (VNI) for reader 1 and 0.88/0.98 (TNC) versus 0.88/0.94 (VNI) for reader 2. Interreader agreement for endoleak detection was substantial (TNC: 0.716, VNI: 0.756). Subjective image noise was comparable between TNC and VNI (4; IQR [4, 5] vs 4; IQR [4, 5], P = 0.44). In the phantom, noise power spectrum peak spatial frequency was similar between TNC and VNI (both f peak = 0.16 mm -1 ). Objective image noise was higher in TNC (12.7 HU) as compared with VNI (11.5 HU). CONCLUSIONS: Endoleak detection and image quality were comparable using VNI images in biphasic CT as compared with TNC images in triphasic CT offering the possibility to reduce scan phases and radiation exposure.

وصف الملف: application/pdf

العلاقة: https://www.zora.uzh.ch/id/eprint/235139/1/ZORA235139.pdfTest; info:pmid/37358359; urn:issn:0020-9996

الإتاحة: https://doi.org/10.5167/uzh-23513910.1097/RLI.0000000000000993Test
https://www.zora.uzh.ch/id/eprint/235139Test/
https://www.zora.uzh.ch/id/eprint/235139/1/ZORA235139.pdfTest

المؤلفون: Mergen, Victor, Ghouse, Sadaf, Sartoretti, Thomas, Manka, Robert, Euler, André, Kasel, Albert M, Alkadhi, Hatem, Eberhard, Matthias

المصدر: Mergen, Victor; Ghouse, Sadaf; Sartoretti, Thomas; Manka, Robert; Euler, André; Kasel, Albert M; Alkadhi, Hatem; Eberhard, Matthias (2023). Cardiac Virtual Noncontrast Images for Calcium Quantification with Photon-counting Detector CT. Radiology: Cardiothoracic Imaging, 5(3):e220307.

مصطلحات موضوعية: Clinic for Diagnostic and Interventional Radiology, Clinic for Cardiology, 610 Medicine & health

الوصف: PURPOSE: To assess the accuracy of aortic valve calcium (AVC), mitral annular calcium (MAC), and coronary artery calcium (CAC) quantification and risk stratification using virtual noncontrast (VNC) images from late enhancement photon-counting detector CT as compared with true noncontrast images. MATERIALS AND METHODS: This retrospective, institutional review board-approved study evaluated patients undergoing photon-counting detector CT between January and September 2022. VNC images were reconstructed from late enhancement cardiac scans at 60, 70, 80, and 90 keV using quantum iterative reconstruction (QIR) strengths of 2-4. AVC, MAC, and CAC were quantified on VNC images and compared with quantification of AVC, MAC, and CAC on true noncontrast images using Bland-Altman analyses, regression models, intraclass correlation coefficients (ICC), and Wilcoxon tests. Agreement between severe aortic stenosis likelihood categories and CAC risk categories determined from VNC and true noncontrast images was assessed by weighted κ analysis. RESULTS: Ninety patients were included (mean age, 80 years ± 8 [SD]; 49 male patients). Scores were similar on true noncontrast images and VNC images at 80 keV for AVC and MAC, regardless of QIR strengths, and VNC images at 70 keV with QIR 4 for CAC (all P > .05). The best results were achieved using VNC images at 80 keV with QIR 4 for AVC (mean difference, 3; ICC = 0.992; r = 0.98) and MAC (mean difference, 6; ICC = 0.998; r = 0.99), and VNC images at 70 keV with QIR 4 for CAC (mean difference, 28; ICC = 0.996; r = 0.99). Agreement between calcification categories was excellent on VNC images at 80 keV for AVC (κ = 0.974) and on VNC images at 70 keV for CAC (κ = 0.967). CONCLUSION: VNC images from cardiac photon-counting detector CT enables patient risk stratification and accurate quantification of AVC, MAC, and CAC.Keywords: Coronary Arteries, Aortic Valve, Mitral Valve, Aortic Stenosis, Calcifications, Photon-counting Detector CT Supplemental material is available for this article © ...

وصف الملف: application/pdf

العلاقة: https://www.zora.uzh.ch/id/eprint/235140/1/ZORA_235140.pdfTest; info:pmid/37404795; urn:issn:2638-6135

الإتاحة: https://doi.org/10.5167/uzh-23514010.1148/ryct.220307Test
https://www.zora.uzh.ch/id/eprint/235140Test/
https://www.zora.uzh.ch/id/eprint/235140/1/ZORA_235140.pdfTest

المؤلفون: Higashigaito, Kai, Mergen, Victor, Eberhard, Matthias, Jungblut, Lisa, Hebeisen, Monika, Rätzer, Susan, Zanini, Bettina, Kobe, Adrian, Martini, Katharina, Euler, André, Alkadhi, Hatem

المصدر: Higashigaito, Kai; Mergen, Victor; Eberhard, Matthias; Jungblut, Lisa; Hebeisen, Monika; Rätzer, Susan; Zanini, Bettina; Kobe, Adrian; Martini, Katharina; Euler, André; Alkadhi, Hatem (2023). CT Angiography of the Aorta Using Photon-counting Detector CT with Reduced Contrast Media Volume. Radiology: Cardiothoracic Imaging, 5(1):e220140.

مصطلحات موضوعية: Clinic for Diagnostic and Interventional Radiology, Epidemiology, Biostatistics and Prevention Institute (EBPI), 610 Medicine & health

الوصف: PURPOSE: To develop and evaluate a low-volume contrast media protocol for thoracoabdominal CT angiography (CTA) with photon-counting detector (PCD) CT. MATERIALS AND METHODS: This prospective study included consecutive participants (April-September 2021) who underwent CTA with PCD CT of the thoracoabdominal aorta and previous CTA with energy-integrating detector (EID) CT at equal radiation doses. In PCD CT, virtual monoenergetic images (VMI) were reconstructed in 5-keV intervals from 40 to 60 keV. Attenuation of the aorta, image noise, and contrast-to-noise ratio (CNR) were measured, and subjective image quality was rated by two independent readers. In the first group of participants, the same contrast media protocol was used for both scans. CNR gain in PCD CT compared with EID CT served as the reference for contrast media volume reduction in the second group. Noninferiority analysis was used to test noninferior image quality of the low-volume contrast media protocol with PCD CT. RESULTS: The study included 100 participants (mean age, 75 years ± 8 [SD]; 83 men). In the first group (n = 40), VMI at 50 keV provided the best trade-off between objective and subjective image quality, achieving 25% higher CNR compared with EID CT. Contrast media volume in the second group (n = 60) was reduced by 25% (52.5 mL). Mean differences in CNR and subjective image quality between EID CT and PCD CT at 50 keV were above the predefined boundaries of noninferiority (-0.54 [95% CI: -1.71, 0.62] and -0.36 [95% CI: -0.41, -0.31], respectively). CONCLUSION: CTA of the aorta with PCD CT was associated with higher CNR, which was translated into a low-volume contrast media protocol demonstrating noninferior image quality compared with EID CT at the same radiation dose.Keywords: CT Angiography, CT-Spectral, Vascular, Aorta, Contrast Agents-Intravenous, Technology Assessment© RSNA, 2023See also the commentary by Dundas and Leipsic in this issue.

وصف الملف: application/pdf

العلاقة: https://www.zora.uzh.ch/id/eprint/232232/1/ZORA_232232.pdfTest; info:pmid/36860835; urn:issn:2638-6135

الإتاحة: https://doi.org/10.5167/uzh-23223210.1148/ryct.220140Test
https://www.zora.uzh.ch/id/eprint/232232Test/
https://www.zora.uzh.ch/id/eprint/232232/1/ZORA_232232.pdfTest

المؤلفون: Jungblut, Lisa, Abel, Frederik, Nakhostin, Dominik, Mergen, Viktor, Sartoretti, Thomas, Euler, André, Frauenfelder, Thomas, Martini, Katharina

المصدر: Jungblut, Lisa; Abel, Frederik; Nakhostin, Dominik; Mergen, Viktor; Sartoretti, Thomas; Euler, André; Frauenfelder, Thomas; Martini, Katharina (2023). Impact of photon-counting-detector-CT derived virtual-monoenergetic-images and iodine-maps on the diagnosis of pleural empyema. Diagnostic and Interventional Imaging, 104(2):84-90.

مصطلحات موضوعية: Clinic for Diagnostic and Interventional Radiology, 610 Medicine & health

الوصف: PURPOSE The purpose of this study was to evaluate the impact of virtual monoenergetic image (VMI) energies and iodine maps on the diagnosis of pleural-empyema with photon-counting-detector computed-tomography (PCD-CT). MATERIALS AND METHODS In this IRB-approved retrospective study, consecutive patients with non-infectious pleural effusion or histopathology-proven empyema were included. PCD-CT examinations were performed on a dual-source PCD-CT in the multi-energy (QuantumPlus) mode at 120 kV with weight-adjusted intravenous contrast-agent. VMIs from 40-70 keV obtained in 10 keV intervals and an iodine map was reconstructed for each scan. CT-attenuation was measured in the aorta, the pleura and the peripleural fat (between autochthonous dorsal muscles and dorsal ribs). Contrast-to-noise (CNR) and signal-to-noise (SNR) ratios were calculated. Two blinded radiologists evaluated if empyema was present (yes/no), and rated diagnostic confidence (1 to 4; not confident to fully confident, respectively) with and without using the iodine map. Sensitivity, specificity and diagnostic confidence were estimated. Interobserver agreement was estimated using an unweighted Cohen kappa test. A one-way ANOVA was used to compare variables. Differences in sensitivity and specificity between the different levels of energy were searched using McNemar test. To compare AUC values DeLong test was performed. McNemar test was performed to compare values for sensitivity and specificity. RESULTS Sixty patients (median age, 60 years; 26 women) were included. A strong negative correlation was found between image noise and VMI energies (r = -0.98; P = 0.001) and CNR increased with lower VMI energies (r = -0.98; P = 0.002). Diagnostic accuracy (96%; 95% CI: 82-100) as well as diagnostic confidence (3.4 ± 0.75 [SD]) were highest at 40 keV. Diagnostic accuracy and confidence at higher VMI energies improved with the addition of iodine maps (P ≤0.001). Overall, no difference in CT attenuation of peripleural fat between patients with empyema and those ...

وصف الملف: application/pdf

العلاقة: https://www.zora.uzh.ch/id/eprint/222990/1/1_s2.0_S2211568422001875_main.pdfTest; info:pmid/36216734; urn:issn:2211-5684

الإتاحة: https://doi.org/10.5167/uzh-22299010.1016/j.diii.2022.09.006Test
https://www.zora.uzh.ch/id/eprint/222990Test/
https://www.zora.uzh.ch/id/eprint/222990/1/1_s2.0_S2211568422001875_main.pdfTest