Linear blended 120 kilovoltage (kV) images (LB120) dual-energy (DE) data sets (50% 100 kV and 50% 140 kV) were compared to noise-optimised virtual monoenergetic image reconstruction (VMI+) at 40 kiloelectron volts (VMI+40). Methods: Similar studies to reduce volume of contrast were done by Wichmann et al. Academia.edu no longer supports Internet Explorer. Results for 1.5 cm slices are statistically evaluated on per slice, per vessel segment ascending aortic, aortic arch, descending and abdominal aorta, right and left iliacal artery (common and external) and per patient level, regarding left-ventricular function and renal impairment. Axial slices of peripheral pulmonary, summarizes the objective image quality assessment fo, ere was a substantial agreement between both radiologists, No false positive or false negative ndings wer, . Purpose: Methods A total of 20 pa, right ventricular dysfunction on echocardiography, mass-index between all three groups (all p, frequency-split technique is used which decomposes both the low keV images (in which iodine pix, high contrast to the surrounding tissue, typ, lower spatial frequency stack at low keV is co. a noise perspective to combine the benets of both images stacks. Purpose: is may be subject to change since administration o, Institute of Clinical Radiology and Nuclear Medicine, University Medical. This single-center retrospective study was HIPAA compliant and institutional review board approved. thought, but there are lingering questions. Compared with standard 100 kVp CTPA, single-source 70 kVp CTPA allows for significant radiation dose savings with comparable SNR and CNR, whereas dual-source 70 kVp CTPA results in a superior objective image quality albeit a reduction of iodine concentration. For these. A radiologic technologist will capture high-resolution CT images while the contrast material flows through the blood vessels. Compared with group A, the average dose-length product was 59% lower in group B (67.3±11.8 vs. 164.7±50.6 mGy cm, P<0.001) and similar between groups A and C (167.7±41.2 mGy cm, P=0.39). Results: [13], Szucs et al. Springer Nature. Access scientific knowledge from anywhere. In detail, the 3, struction algorithm was set to a strength level of three for all three CTP, post-processing and measurements in a timel, right pulmonary artery) and two peripheral pulmonary arteries (one lower and one u, by a radiology resident (M.M), as previously described, air (for DE datasets in the VPS images) in order t, determine the SNR and CNR with the erector spinae m, the averages of the three central pulmona, prior to the subjective image quality assessmen, described for chest CT examinations in the Eur, used for calculating the required sample size usin, Statistical analysis was performed using JMP 10.0 (SAS In, deviation and ordinal variables as median with a 25% to 75% in, groups and serum creatinine time points w, comparison between VMS datasets repeated ANOV, sensus reading was used for statistical signicance assessment between the three DSCT pro, specicity and accuracy were calculated on a per-patient base for the 40, were rated as diagnostic. The number of end-stage renal disease patients in the world was increasing year by year. Low-contrast agent dose dual-energy CT monochroma, . Conclusions: The Challenges in Assessing Contrast-Induced Nephropathy: Where Are We Now? Subjective image quality was evaluated using a five-grade scale, and diagnostic accuracy was assessed. Premium PDF Package. Image quality, diagnostic accuracy and radiation dose were evaluated and compared. Purpose of review: Download PDF Package. The authors recommend routine reconstruction of VM images at 50 keV when using dual-energy CT to exploit the increased contrast properties. Likewise, there was no signicant dierence in the median imag, negative ndings were observed, resulting in a sensiti, dierences to the baseline evaluation for the standar, serum creatinine levels of those patients with acute kidney failure d, sample size, it has to be noted that the s, ard CM dose. After checking “matches,” the director of the transplant The current standard of care for members with suspected pulmonary embolism is a spiral CT scan, also called a CTA, CT PA (computed tomography pulmonary angiography), MDCT (multidector CT) or helical CT scan. CT angiography has become the gold standard for evaluation of suspected pulmonary embolism; however, continuous evolution in radiology has led to new imaging approaches that offer improved options for detection and characterization of pulmonary embolism while exposing patients to lower contrast and radiation dose. Alternatively, repeat CT pulmonary angiography or conventional pulmonary angiography may be performed to evaluate for pulmonary embolism. Advances in knowledge To assess image quality, radiation dose, and diagnostic accuracy of 70-kVp high-pitch computed tomography pulmonary angiography (CTPA) using 40 mL contrast agent and sinogram affirmed iterative reconstruction (SAFIRE) compared to 100-kVp CTPA using 60 mL contrast agent and filtered back projection. CT Pulmonary Angiography: Quantification of Pulmonary Embolus as a Predictor of Patient Outcome—Initial Experience1. Conclusions To the fullest extent permitted by law, Springer Nature makes no warranties, representations or guarantees to Users, either express or implied. Recent findings: Sixty patients had PE and 60 patients had no PE at CTA. CT is widely used as an integral part of diagnostic evaluation of patients with suspected SSc-PAH. 1023-1029 Article Download PDF View Record in Scopus Google Scholar Mannheim – Heidelberg University, Mannheim. Improved contrast attenuation with VM imaging at lower kiloelectron volt levels enables better delineation and diagnostic accuracy in the detection of various vascular or oncologic abnormalities. Sensitivity analyses examining only patients with stable prescan serum creatinine levels and incorporating intravenous fluid administration at the time of the CT scan into the model were also performed. Patients between the ages of 18 and100 with a CTPA … PDF. 73-year-old woman with a peripheral pulmonary embolism (white arrows). The values of urea nitrogen and serum creatinine were significantly higher than those in the sham-operated group (P. In this article, the authors discuss the technical background and summarize the current body of literature regarding virtual monoenergetic (VM) images derived from dual-energy CT data, which can be reconstructed between 40 and 200 keV. Objectives A total of 6902 patients (4496 CKD stage III, matched: 1220 contrast and 1220 noncontrast; 2086 CKD stage IV-V, matched: 491 contrast and 491 noncontrast) were included in the study. In patients with acute or chronic renal insufficiency, Meyer et al. The remaining seven rats only received renal capsule stripping instead of nephrectomy (the sham-operated group). In 2008, all CTPA were being performed on 16-slice A greater proportion of patients underwent ventilation/perfusion scanning in larger hospitals compared with smaller hospitals (13.1% versus 7.3%, P<0.001). feasibility and eect on image quality and iodine dose. Results: Rates of AKI, 30-day emergent dialysis, and mortality were compared between contrast and noncontrast groups. The imaging modalities included computed tomography pulmonary angiography, ventilation/perfusion scanning, pulmonary angiography, a combination of these tests, or PE signs and symptoms plus imaging-confirmed proximal deep vein thrombosis but no chest imaging. (email: Content courtesy of Springer Nature, terms of use apply. Materials and methods: Objective: The detection rate of pulmonary emboli (PE) with computed tomography angiography (CTA) using either a standard or a low-dose protocol, combining reduced radiation exposure and iodine delivery rate, was retrospectively analyzed in a matched cohort of 120 patients. Subsequently, virtual monoenergetic images (MEI+) were reconstructed at five different keV levels (40, 55, 70, 85, 100) and compared to the standard linearly blended (M_0.8) CTpv images. sidered the gold-standard diagnostic modality in patients with sus, undergoing several CT examinations within a few da, Over the last decade, low peak-kilovoltage (kV, ciency of x-ray tubes with insucient phot. 47 patients (25 females) with mean age 69 years (range 41–82 years) referred for contrast-enhanced chest CT were prospectively included in this Phase IV clinical drug trial. To view a copy of this license, visit. After propensity score adjustment, rates of AKI, emergent dialysis, and mortality were not significantly higher in the contrast group than in the noncontrast group in either CKD subgroup (CKD stage III: OR, 0.65-1.00; P<.001-.99 and CKD stage IV-V: OR, 0.93-2.33; P=.22-.99). In 2000, CTPAs were performed on single or 4 – slice scanners (HiSpeed, GE Healthcare, UK). These Terms will prevail over any conflict or ambiguity with regards to the relevant terms, a site licence or a personal subscription, (to the extent of the conflict or ambiguity only). 1,2 Since the 1990s, CT pulmonary angiography (CTPA) has become the method of choice for imaging in suspected PE. Computed MEI+ at low keV levels allow for improved vessel contrast and visualisation of incidental pulmonary embolism in patients with portal-venous phase CT scans by substantially increasing CNR and SNR. Introduction. 2 Eighty-seven diabetes mellitus patients with increased serum creatinine level were enrolled at the Department of Cardiology of Fushun Central Hospital from May 2005 to May 2007. Pulmonary angiography (or pulmonary arteriography) is medical fluoroscopic procedure used to visualize the pulmonary arteries and much less frequently, the pulmonary veins.. A region of-interest measurement may be helpful if the attenuation is greater than 78 HU. Not only does it allow demonstration of associated interstitial lung disease (ILD) but CT pulmonary angiography (CTPA) also permits exclusion of significant thromboembolic disease. Dual-energy computed tomography (DECT) has evolved from a research tool to an established clinical imaging modality since its first commercial introduction in the mid-2000s. The median number of examinations visually scored concerning pulmonary embolism as good–excellent was 47/47 (range 44–47); adequate 0/47 (0–3) and non-diagnostic 0/47 (range 0–0). Subjective image quality showed no difference between the two groups (P = 0.559) with good interobserver agreement (κ = 0.647). Average SNR and CNR were significantly higher for group C (21.5±4.7 and 19.0±4.5, respectively) compared with groups A (18.3±3.5 and 15.8±3.4, respectively) and B (17.3±5.8 and 15.6±5.5, respectively; all Ps≤0.001). An exploratory objective of this study was t, All technical and personal data were removed from the images, A two-sided binominal test with a signicance level of 0.05 and a power of 0.8 wer, Simplied image reconstruction work ow of the monoenergetic recon, 73-year-old woman with a peripheral pulmonary embolism (white arrows). 1 The serum creatinine level increased significantly less in patients in the iodixanol group than in the iopromide group (P < 0.05). These Terms are supplementary and will apply in addition to any applicable website terms and conditions, a relevant site licence or a personal, subscription. 14,15. Enter the email address you signed up with and we'll email you a reset link. Objectives To perform CT pulmonary angiography (CTPA) using a minimal amount of iodinated contrast media. Computed tomographic pulmonary angiography (CTPA) using helical (or spiral) CT has emerged as the preferred diagnostic test for PE. Free PDF. Once a threshold of 100 Ho, reconstruction (IR) algorithm. For reduction of beam-hardening artifacts, VM imaging at 120 keV is useful for the initial assessment. By combining several procedures in a CTPA protocol, the contrast media dose can be minimized. Carlos, K.E. Springer Nature supports a reasonable amount of sharing of research papers by authors, subscribers and authorised users (“Users”), for small-, scale personal, non-commercial use provided that all copyright, trade and service marks and other proprietary notices are maintained. To browse Academia.edu and the wider internet faster and more securely, please take a few seconds to upgrade your browser. Criteria to be used for Chest CTA or a CT is requested for Pulmonary Emboli which cannot be approved based on Interqual or Milliman criteria. Here we present STARD 2015, an updated list of 30 essential items that should be included in every report of a diagnostic accuracy study. Intravenous contrast material administration was not associated with excess risk of AKI acute kidney injury , dialysis, or death, even among patients with comorbidities reported to predispose them to nephrotoxicity. 100 further patients were either examined with a standard CTPA protocol or a standard DE CTPA (32 g iodine). CT pulmonary angiography and triple rule-out scanning protocols All patients were scanned on a second generation of dual-source CT scanner (Siemens Definition Flash, Siemens Healthcare, Forchheim, Germany). All participants underwent a study specific CTPA in addition to the chest CT. 2 Severe side effects occurred in one patient of the iodixanol group and six patients of the iopromide group. Signal-to-noise ratio and contrast-to-noise ratio were calculated. The participants received 80 mg I/kg body weight Iohexol contrast media using a preparatory saline bolus, a dual flow contrast/saline bolus and a saline flush, and a scanner protocol with 80 kVp dual source high-pitch mode. The aim of this study was to (a) build a diagnostic CT model and (b) test its prognostic significance. Method: Conventional computed tomographic (CT) scanning is, however, at a disadvantage because of its inability to obtain multiplanar images. For the localizations with emboli, both the sensitivity (83.7% at 80 kVp and 83.6% at 120 kVp; P = 0.921) and the specificity (97.2%, at 80 kVp and 97.8% at 120 kVp; P = 0.463) were not significantly different at the 2 tube voltages. We suggest that CIN is likely real but is rare and offer directions for future study. The introduction of dual-energy CT has resulted in the ability to add functional and prognostic information beyond the morphologic assessment of the pulmonary arteries and potentially offer improved image quality without additional radiation burden. However, little is known about the choice of the diagnostic modalities in practice. During his initial hospitalization, the patient receives The scanning protocol for CTPA was as follows: detector Results Patients with preexisting diabetes mellitus, congestive heart failure, or chronic or acute renal failure were identified as high-risk patient subgroups for nephrotoxicity. The pulmonary vasculature may be evaluated with various invasive and noninvasive methods. It may be due to a variety of embolic materials and result in a wide spectrum of clinical presentations, making the diagnosis difficult. Axial slices of peripheral pulmonary arteries of a low contrast media dual-energy CTPA: (A) mixed 0.8-weighted virtual polyenergetic spectral (VPS) image, and virtual monoenergetic spectral (VMS) images at a level of 40 keV (B), 50 keV (C), 60 keV (D), 70 keV (E), 80 keV (F), 90 keV (G) and 100 keV (H). Moreover, we highlight interesting experimental and preclinical research topics that may become clinically available in the future. Results: MDCT angiography of the pulmonary arteries: inuence of body weight, body mass index, and scan length on, This article is licensed under a Creative Commons Attribution 4.0 International, http://creativecommons.org/licenses/by/4.0/. RESULTS:Ten weeks after model construction, the bodyweight of rats in the model group was significantly lower than that in the sham-operated group. To examine the effect of intravenous iodinated contrast material administration on the subsequent development of acute kidney injury (AKI), emergent dialysis, and short-term mortality using a propensity score-adjusted analysis of computed tomographic scan recipients with chronic kidney disease (CKD). 4841 slices with mean density 280.0 ± 63 HU are analyzed. The choice of the imaging modality for diagnosis of pulmonary embolism (PE) could be influenced by provider, patient or hospital characteristics, or over time. Introduction: Patients in the contrast and noncontrast groups were compared following propensity score-based 1:1 matching to reduce intergroup selection bias. Virtual monoenergetic imaging (VMI) and multi-material decomposition (MMD) imaging (see Chap. The objective of our study was to exposit the shifting perspectives on contrast-induced nephropathy (CIN) for IV low-osmolar iodinated contrast media. a call of encouragement from the President of the United States. Fir, a decision-making with sucient diagnostic condence for co, scans were performed on dierent CT scanner, and can be used to save contrast media when using VMS reco, tion in diagnostic accuracy, vessel opacica, ideal when reducing the total iodine amount down to 5.4, patients undergoing single-pass dual-energy comp. The mean attenuation ± standard deviation in the pulmonary trunk was 325 ± 72 Hounsfield unit (range 165–531 Hounsfield unit). You can download the paper by clicking the button above. Over the past two decades, however, catheter angiography has become almost entirely supplanted by CT angiography (CTA), which is now the … To perform CT pulmonary angiography (CTPA) using a minimal amount of iodinated contrast media. Noise-optimized monoenergetic post-processing impro, . The possibility to characterize the composition of different human tissues and the quantification of certain materials like iodine, calcium, or fat have shown clinical benefit for various body regions. CT Scan angiography of the thoracic aorta (SIEMEN) - CLVT Động mạch chủ ngực - Duration: 12:19. To illustrate the role of pulmonary perfusion in the diagnosis of acute and chronic pulmonary thromboembolism. Rights reserved, using a standard CM-, as well as a reduced CM-p, VMS soware technique, which lacks noise com, duced noise optimized VMS algorithm allows for a further reduction o, with suspected PE were equally (1:1 ratio) randomized either to, quality (contrast-to-noise-ratio [CNR] and im, arteries and overall subjective image quality, polyenergetic spectral (VPS) images. may revoke this licence to you at any time and remove access to any copies of the Springer Nature journal content which have been saved. ORIGINAL ARTICLE A retrospective comparison of smart prep and test bolus multi-detector CT pulmonary angiography protocols Tara Suckling1, Tony Smith2 & Warren Reed3 1Medical Imaging Department, Tamworth Rural Referral Hospital, Tamworth, New South Wales, Australia 2University Department of Rural Health, The University of Newcastle, Tamworth, New South Wales, Australia Objective CT pulmonary angiography (CTPA) is one of the most commonly ordered CT imaging tests. Mean patient weight was 71 kg (range 50–85 kg). Pulmonary Angiography Kyung Cho Nils Kucher Although right heart catheterization was first described in 1929,1 angiographic visualization of the pulmonary arteries was not performed until 1938.2 Initially, pulmonary angiography was performed using a nonselective technique (by intravenous injection of contrast material), to avoid venous cutdown, catheter manipulation, and fluoroscopy. Chest diameter, dose-length product, intravascular signal attenuation, image noise, signal to noise ratio (SNR), and contrast to noise ratio (CNR) were compared. Conclusions: Impact of sinogram armed iterative reconstruction (SAFIE) algorithm on image q, . License, visit Stojanovska, R.C imposed by law, Springer Nature injury are still controversially discussed a. Load at CT pulmonary angiography ( CTPA ) may obscure thrombus this chapter, we discuss the potential pitfalls with... 325 ± 72 Hounsfield unit ) completeness and transparency in reporting of diagnostic accuracy studies Springer! Using a minimal amount of contrast were done by Wichmann et al work flow of the arm factor a! 0.647 ) additionally, the attenuation of iodine in low-kVp CT protocols is used for.! Insufficiency, Meyer et al for reducing radiation exposure an, in Contrast-Induced. Non-Thrombotic PE does not represent a distinct clinical syndrome were included in this.. 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