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1.
ObjectivesTo study the diagnostic performance of the ratio between the Duke jeopardy score (DJS) and the minimal lumen diameter (MLD) (DJS/MLDCT ratio) as assessed by coronary computed tomographic angiography (CTA) for differentiating functionally significant from non-significant coronary artery stenoses, with reference to invasive fractional flow reserve (FFR).MethodsPatients who underwent both coronary CTA and FFR measurement during invasive coronary angiography (ICA) within 2 weeks were retrospectively included in the study. Invasive FFR measurement was performed in patients with intermediate to severe coronary stenoseis. DJS/MLDCT ratio and anatomical parameters were recorded. Lesions with FFR ≤0.80 were considered to be functionally significant.ResultsOne hundred and sixty-one patients with 175 lesions were included into the analysis. Diameter stenosis in CT, area stenosis, plaque burden, lesion length (LL), ICA-based stenosis degree, DJS, LL/MLD4 ratio, DJS/MLA ratio as well as DJS/MLD ratio were all significantly different between hemodynamically significant and non-significant lesions (p<0.05 for all). ROC curve analysis determined the optimal cut-off value for DJS/MLDCT ratio to be 1.96 (area under curve = 0.863, 95 % confidence interval = 0.803–0.910), yielding a high diagnostic accuracy (86.9%, 152/175).ConclusionsIn coronary artery stenoses detected by coronary CTA, the DJS/MLD ratio is able to predict hemodynamic relevance.  相似文献   

2.
BackgroundRecent studies demonstrated a significant improvement in the diagnostic performance of coronary CT angiography (CCTA) for the evaluation of in-stent restenosis (ISR). However, coronary stent assessment is still challenging, especially because of beam-hardening artifacts due to metallic stent struts and high atherosclerotic burden of non-stented segments. Adenosine-stress myocardial perfusion assessed by CT (CTP) recently demonstrated to be a feasible and accurate tool for evaluating the functional significance of coronary stenoses in patients with suspected coronary artery disease (CAD). Yet, scarce data are available on the performance of CTP in patients with previous stent implantation.Aim of the studyWe aim to assess the diagnostic performance of CCTA alone, CTP alone and CCTA plus CTP performed with a new scanner generation using quantitative invasive coronary angiography (ICA) and invasive fractional flow reserve (FFR) as standard of reference.MethodsWe will enroll 300 consecutive patients with previous stent implantation, referred for non-emergent and clinically indicated invasive coronary angiography (ICA) due to suspected ISR or progression of CAD in native coronary segments. All patients will be subjected to stress myocardial CTP and a rest CCTA. The first 150 subjects will undergo static CTP scan, while the following 150 patients will undergo dynamic CTP scan. Measurement of invasive FFR will be performed during ICA when clinically indicated.ResultsThe primary study end points will be: 1) assessment of the diagnostic performance (diagnostic rate, sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy) of CCTA, CTP, combined CCTA-CTP and concordant CCTA-CTP vs. ICA as standard of reference in a territory-based and patient-based analysis; 2) assessment of sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of CCTA, CTP, combined CCTA-CTP and concordant CCTA-CTP vs. invasive FFR as standard of reference in a territory-based analysis.ConclusionsThe ADVANTAGE study aims to provide an answer to the intriguing question whether the combined anatomical and functional assessment with CCTA plus CTP may have higher diagnostic performance as compared to CCTA alone in identifying stented patients with significant ISR or CAD progression.  相似文献   

3.
BackgroundCoronary computed tomography angiography (CCTA) not only provides information regarding luminal stenoses but also allows for visualization of mural atheromatous changes (coronary plaques).ObjectiveWe sought to elucidate whether plaques seen on CCTA enable prediction of 2-year outcomes in patients with suspected and known coronary artery disease (CAD).MethodsOf 3015 patients who underwent CCTA, the images and 2-year clinical courses of 2802 patients were independently analyzed. The primary endpoint was the composite of all-cause death and acute coronary syndrome.ResultsDuring the 2-year observation period, 49 (1.7%) patients developed the primary outcome. The 2-year rates of the primary outcome in the normal (n = 515, no mural lesions), calcium (n = 654, calcified lesion alone), and plaque groups (n = 1633, presence of noncalcified or partially calcified plaques) were 0.2%, 2.0%, and 2.1%, respectively (P = 0.0028). Adverse plaque features such as low attenuation, positive remodeling, spotty calcification, and the napkin-ring sign (low-attenuation core with a higher-attenuation rim) were assessed by an independent core laboratory. Stepwise multivariate Cox proportional hazard analysis showed that a plaque with two or more characteristics (adjusted hazard ratio, 1.98; 95% confidence interval, 1.09–3.60; P = 0.0254), age of ≥67 years (mean), statin treatment after CCTA, and obstructive stenosis remained independent predictors of the primary outcome.ConclusionsPlaque imaging in CCTA has predictive value for the 2-year outcome and is a useful identifier for high-risk patients among those with known and suspected CAD.  相似文献   

4.
AimsNon-invasive fractional flow reserve derived from coronary CT angiography (FFRCT) has been shown to be predictive of lesion-specific ischemia as assessed by invasive fractional flow reserve (FFR). However, in practice, clinicians are often faced with an abnormal distal FFRCT in the absence of a discrete obstructive lesion. Using quantitative plaque analysis, we sought to determine the relationship between an abnormal whole vessel FFRCT (V-FFRCT) and quantitative measures of whole vessel atherosclerosis in coronary arteries without obstructive stenosis.MethodsFFRCT was calculated in 155 consecutive patients undergoing coronary CTA with ≥25% but less than 70% stenosis in at least one major epicardial vessel. Semi-automated software was used to quantify plaque volumes (total plaque [TP], calcified plaque [CP], non-calcified plaque [NCP], low-density non-calcified plaque [LD-NCP]), remodeling index [RI], maximal contrast density difference [CDD] and percent diameter stenosis [%DS]. Abnormal V-FFRCT was defined as a minimum value of ≤0.75 across the vessel (at the most distal region where FFRCT was computed).ResultsVessels with abnormal V-FFRCT had higher per-vessel TP (554 vs 331 mm3), CP (59 vs 25 mm3), NCP (429 vs 295 mm3), LD-NCP (65 vs 35 mm3) volume and maximum CDD (21 vs 14%) than those with normal V-FFRCT (median, p < 0.05 for all). Using a multivariate analysis to adjust for CDD and %DS, all measures of plaque volume were predictive of abnormal V-FFRCT (OR 2.09, 1.36, 1.95, 1.95 for TP, CP, NCP and LD-NCP volume, respectively; p < 0.05 for all).ConclusionAbnormal V-FFRCT in vessels without obstructive stenosis is associated with multiple markers of diffuse non-obstructive atherosclerosis, independent of stenosis severity. Whole vessel FFRCT may represent a novel measure of diffuse coronary plaque burden.  相似文献   

5.
BackgroundTo optimize spectral coronary computed tomography angiography (CTA) for quantification of coronary artery plaque components.Materials and methodsFifty-one subjects were prospectively enrolled (88.2% male) (NCT02740699). Dual energy coronary CTA was performed at 90/Sn150 kVp using a 3rd generation dual-source CT scanner (SOMATOM Force, Siemens Healthcare). Dual energy images were reconstructed with a) linear mixed blending of 90 and Sn150 kVp data, b) virtual monoenergetic algorithm from 40 to 150 keV (at 10- keV intervals), and c) noise-optimized virtual monoenergetic algorithm from 40 to 150 keV. Image noise, iodine signal-to-noise-ratio (SNR), and contrast-to-noise ratio (CNR) for calcified and non-calcified plaque were measured. Qualitative readings of image quality were performed. Semi-automated software (QAngioCT, Medis) was used to quantify coronary plaque. Linear mixed-models that account for within-subject correlation of plaques were used to compare the results.Results100–150 keV noise-optimized virtual monoenergetic images had lower image noise than linear mixed images (all P < 0.05). The highest iodine SNR was achieved in 40 keV noise-optimized virtual monoenergetic images (33.3 ± 0.6 vs 23.3 ± 0.7 for linear mixed images, P < 0.001). 40–70 keV noise-optimized virtual monoenergetic images and 70 keV virtual monoenergetic images had superior coronary plaque CNR versus linear mixed images (all P < 0.01) with a maximum improvement of 20.1% and 22.7% for calcified plaque and non-calcified plaque (38.8 ± 2.2 vs 32.3 ± 2.3 and 17.3 ± 1.3 vs 14.1 ± 1.4, respectively). Using 90/Sn150 kVp linear mixed images as a reference, the plaque quantity was similar for 70 keV noise-optimized virtual monoenergetic images whereas low keV images (e.g. 40 keV) yielded significantly higher coronary plaque volumes (all P < 0.001).ConclusionSpectral coronary CTA with low energy (40–70 keV) post-processing can improve the CNR of coronary plaque components. However, low energies (such as 40 keV) resulted in different absolute volumes of coronary plaque compared to “conventional” mixed 90/Sn150 kVp images.  相似文献   

6.
BackgroundTo determine the impact of high-pitch spiral acquisition on radiation dose and cardiovascular disease (CVD) risk stratification by coronary artery calcium (CAC) assessment with computed tomography in individuals with a high heart rate.MethodsOf the ROBINSCA trial, 1990 participants with regular rhythm and heart rates >65 beats per minute (bpm) were included. As reference, 390 participants with regular heart rates ≤65 bpm were used. All participants underwent prospectively electrocardiographically(ECG)-triggered imaging of the coronary arteries using dual source CT at 120 kVp, 80 ref mAs using both high-pitch spiral mode and sequential mode. Radiation dose, Agatston score, number of positive scores, as well as median absolute difference of the Agatston score were determined and participants were stratified into CVD risk categories.ResultsA similar percentage of participants with low heart rates and high heart rates had a positive CAC score in data sets acquired in high-pitch spiral (low heart rate: 57.7%, high heart rate: 55.8%) and sequential mode (58.0%, 54.7%, p = n.s.). The median absolute difference in Agatston scores between acquisition modes was 14.2% and 9.2%, for the high and low heart rate groups, respectively. Excellent agreement for risk categorization between the two data acquisition modes was found for the high (κ = 0.927) and low (κ = 0.946) heart rate groups. Radiation dose was 48% lower for high-pitch spiral versus sequential acquisitions.ConclusionRadiation dose for the quantification of coronary calcium can be reduced by 48% when using the high-pitch spiral acquisition mode compared to the sequential mode in participants with a regular high heart rate. CVD risk stratification agreement between the two modes of data acquisition is excellent.  相似文献   

7.
BackgroundCoronary stenosis and plaque evaluation by coronary computed tomography angiography (CTA) may contribute to identify hemodynamically relevant lesions. We evaluated the most stenotic lesion including plaques proximal to it versus a total vessel analyses combined with stenosis for ischemia.MethodsPatients scheduled for clinically indicated invasive coronary angiography (ICA) for suspected coronary artery disease underwent coronary CTA and ICA including fractional flow reserve (FFR) as part of the NXT trial (clinicaltrials.gov NCT01757678). Stenoses were visually graded ≤50%, 51–70%, and >70% on coronary CTA. Semi-automated plaque analyses were performed using a proximal to the FFR pressure sensor location (including the most severe lesion to the coronary ostium) versus a total vessel (vessel diameter ≥2 mm) approach. Coronary stenosis and plaque parameters were evaluated for discrimination of ischemia by logistic regressions and combined models analyzed using receiver operating characteristics (ROC) with invasive FFR≤ 0.80 as reference standard.ResultsIn 254 patients, mean (±SD) age 64 (±10) years, 64% male, a coronary CTA stenosis >50% was present in 239 (49%) vessels. Invasive FFR was ≤0.80 in 100 (21%) vessels. Coronary stenosis severity and low-density non-calcified plaque (LD-NCP) volume were independent predictors of ischemia in the “proximal” and “total-vessel” analyses. Stenosis severity + total vessel LD-NCP assessment performed better than stenosis severity + proximal LD-NCP evaluation (Area under curve [AUC] (95%CI): 0.83 (0.78–0.87) vs 0.81 (0.76–0.86), p-value = 0.009), whereas stenosis severity + proximal LD-NCP performed better than stenosis alone (AUC (95%CI): 0.81 (0.76–0.86) vs 0.78 (0.73–0.83), p-value = 0.019).ConclusionAdding total vessel high-risk plaque volume to stenosis severity improves discrimination of ischemia in coronary CTA performed in patients with stable angina pectoris.  相似文献   

8.
Multiple dose reduction techniques have been introduced for coronary artery calcium (CAC) computed tomography (CT), but few have emerged into clinical practice while an increasing number of patients undergo CAC scanning. We sought to determine to what extend the radiation dose in CAC CT can be safely reduced without a significant impact on cardiovascular disease (CVD) risk stratification. A systematic database-review of articles published from 2002 until February 2018 was performed in Pubmed, WebOfScience, and Embase. Eligible studies reported radiation dose reduction for CAC CT, calcium scores and/or risk stratification for phantom or patient studies. Twenty-eight studies were included, under which 17 patient studies, 10 phantom/ex-vivo studies, and 1 study evaluated both phantom and patients. Dose was reduced with tube voltage reduction and tube current reduction with and without iterative reconstruction (IR), and tin-filter spectral shaping. The different dose reduction techniques resulted in varying final radiation doses and had varying impact on CAC scores and CVD risk stratification. In 78% of the studies the radiation dose was reduced by ≥ 50% ranging from (CTDIvol) 0.6–5.5 mGy, leading to reclassification rates ranging between 3% and 21%, depending on the acquisition technique. Specific dose reduced protocols, including either tube current reduction and IR or spectral shaping with tin filtration, that showed low reclassification rates may potentially be used in CAC scanning and in future population-based screening for CVD risk stratification.  相似文献   

9.
PurposeThe objectives of this study were to describe fracture morphology resulting from common loading mechanisms such as bending and torsion in immature bone and to identify differences in the energy required to produce various fracture types under these two loading mechanisms using an immature porcine animal model.MethodsTwenty-six in vitro immature porcine femora were mechanically tested in 3-point-bending and torsion. Femur specimens were tested with and without soft tissue and at both quasi-static and dynamic loading rates. Bone geometry and density measures were determined for each femur using dual-energy x-ray absorptiometry and plain film x-rays. Failure load, stiffness, and energy to failure were determined for each specimen from the load-displacement history from mechanical tests.Results3-point bending tests resulted in 10 transverse fractures and 2 oblique fractures. Torsion tests resulted in spiral fractures. Mean energy required to produce transverse fractures (3.32 Nm) was double that associated with spiral fractures (1.66 Nm). In bending, specimens with soft tissue intact required significantly greater energy to fracture (4.40 Nm) than specimens with soft tissue removed (2.92 Nm). Torsional loading rate did not significantly affect energy to fracture.ConclusionsFracture morphology is dependent upon loading conditions. Energy to failure allows for comparison across various loading conditions, and thus offers an effective means of characterizing fracture thresholds for a wide range of scenarios. Consideration should be given to whether or not soft tissue is left intact when conducting experiments using whole bone specimens given its influence on energy to failure.  相似文献   

10.
Until recently, iodine-124 was not considered to be an attractive isotope for medical applications owing to its complex radioactive decay scheme, which includes several high-energy gamma rays. However, its unique chemical properties, and convenient half-life of 4.2 days indicated it would be only a matter of time for its frequent application to become a reality. The development of new medical imaging techniques, especially improvements in the technology of positron emission tomography (PET), such as the development of new detectors and signal processing electronics, has opened up new prospects for its application. With the increasing use of PET in medical oncology, pharmacokinetics, and drug metabolism, 124I-labeled radiopharmaceuticals are now becoming one of the most useful tools for PET imaging, and owing to the convenient half-life of I-124, they can be used in PET scanners far away from the radionuclide production site. Thus far, the limited availability of this radionuclide has been an impediment to its wider application in clinical use. For example, sodium [124I]-iodide is potentially useful for diagnosis and dosimetry in thyroid disease and [124I]-M-iodobenzylguanidine ([124I]-MIBG) has enormous potential for use in cardiovascular imaging, diagnosis, and dosimetry of malignant diseases such as neuroblastoma, paraganglioma, pheochromocytoma, and carcinoids. However, despite that potential, both are still not widely used. This is a typical scenario of a rising new star among the new PET tracers.  相似文献   

11.
Three cases with mass like lesions (pseudotumours) surrounding atheromatous coronary arteries were referred to the Royal Brompton Hospital for expert pathology review. All were males with mean age 74 years (range 55–91). In all cases, coronial autopsies were carried out for sudden deaths in the community. Past medical histories of note were hypertension (N = 2) and ischaemic heart disease (N = 1), with one patient having a past history of aortic aneurysm repair.At autopsy, firm, white and whorled masses surrounded both right and left coronary arteries ranging in size from 9 to 25 mm in diameter. Each coronary artery had intimal atheroma with associated stenosis ranging from moderate to severe. A thrombus was identified in one case.Histological sections showed a mixed inflammatory infiltrate extending from the media into the adventitia of each coronary artery, composed predominantly of plasma cells and lymphocytes with rare neutrophils and eosinophils. There was accompanying dense fibrosis accounting for approximately 50% of the mass size on microscopic examination of slides. The presence of intimal circumferential atheroma was confirmed in all cases.Immunohistochemical studies showed staining with IgG4 in two of three cases.Atheroma may be associated with mild chronic inflammation present in the intima or associated with plaques and adventitia. The differential diagnosis for coronary artery inflammatory masses would include vasculitis, syphilis, inflammatory pseudotumor and IgG4 associated disease.This is the first report of isolated coronary artery IgG4 related disease in association with atheroma.  相似文献   

12.
BackgroundPulmonary nodules (PN) are frequently detected incidentally during coronary computed tomography angiography (CTA). We evaluated whether the 2017 Fleischner Society guidelines may result in a decrease of follow-up testing of incidental PN as compared to prior guidelines in patients undergoing coronary CTA.MethodsWe conducted a retrospective study of a registry of emergency department patients who underwent coronary CTA for acute coronary syndrome assessment between 2012 and 2017. Based on guidelines, patients <35 years, history of cancer, or prior exams showing stability of PN were excluded. Patients >60 years, history of smoking, irregular/spiculated PN morphology, or PN size >20 mm were classified as high-risk for lung cancer. Radiological findings pertaining to PN were identified (PN size, morphology, quantity) through review of radiology reports. PN follow-up recommendations were established using 2017 Fleischner Society Guidelines and compared with prior guidelines for solid (2005) and subsolid (2013) PN. Data were analyzed with Student's t-test.ResultsThe registry included 2066 patients (female 45.1%, 52.9 ± 11.0 years), of which 578 (28.0%) reported PN. 438 of those (21.2%) were eligible for guideline-based follow-up evaluation. 205 (4 6.8%) were classified as high-risk for lung cancer. 2017 guidelines reduced the number of individuals requiring follow-up by 64.5%, from 264 (12.8%) to 94 patients (4.5%) when compared to prior guidelines (p < 0.001). The minimum number of follow-up chest CTs decreased by 55.8% from 430 to 190 (p < 0.001).ConclusionApplication of the 2017 Fleischner Society Guidelines resulted in a significant decrease of follow-up testing for incidental PN in patients undergoing coronary CTA for suspected acute coronary syndrome.  相似文献   

13.
PurposeTo analyze long-term outcomes in patients bridged/downstaged to orthotopic liver transplantation (OLT) by transarterial chemoembolization (TACE) or yttrium-90 radioembolization (Y90) for hepatocellular carcinoma (HCC).Methods172 HCC patients who underwent OLT after being treated with transarterial liver-directed therapies (LDTs) (Y90: 93; TACE: 79) were identified. Pre-LDT and pre-OLT clinical/imaging/laboratory characteristics including United Network for Organ Sharing (UNOS) staging and alpha-fetoprotein values (AFP) were tabulated. Post-OLT HCC recurrence was assessed by imaging follow-up per standard of care. Recurrence-free (RFS) and overall survival (OS) were calculated. Uni/multivariate and sub-stratification analyses were performed.ResultsTime-to-OLT was longer in the Y90 group (Y90: 6.5 months; TACE: 4.8 months; p = 0.02). With a median post-OLT follow-up of 26.1 months (IQR: 11.1–49.7), tumor recurrence was found in 6/79 (8%) TACE and 8/93 (9%) Y90 patients. Time-to-recurrence was 26.6 (CI: 7.0–49.5) and 15.9 months (CI: 7.8–46.8) for TACE and Y90, respectively (p = 0.48). RFS (Y90: 79 months; TACE: 77 months; p = 0.84) and OS (Y90: 57% alive at 100 months; TACE: 84.2 months; p = 0.57) were similar. 54/155 patients (Y90: 29; TACE: 25) were downstaged to UNOS T2 or less. RFS hazard ratios for patients downstaged to ≤T2 versus those that were not were 0.6 (CI: 0.33–1.1) and 1.7 (CI: 0.9–3.1) respectively (p = 0.13). 17/155 patients (Y90: 8; TACE: 9) that were >T2 were downstaged to UNOS T2 or less (within transplant criteria). Distribution (unilobar/bilobar), AFP, and pre-transplant UNOS stage affected RFS on univariate analyses.ConclusionDespite longer time-to-OLT for Y90 patients, post-OLT outcomes were similar between patients bridged or downstaged by TACE or Y90. A trend towards improved RFS for downstaged patients was identified.  相似文献   

14.
PurposeTo determine the value of multislice CT coronary artery calcification (CAC) scoring in the prediction of future cardiac events in known chronic kidney disease (CKD) patients using conventional coronary angiography as the standard reference.Patients and methodsFifty-eight patients with CKD on hemodialysis underwent CT CAC scoring using multislice scanner and conventional coronary angiography. Results of CAC scoring were compared to the findings of conventional coronary angiography.ResultsMean CAC scoring in patients with significant coronary arteries stenotic lesions was higher than in patients with no significant coronary arteries stenotic lesions with significant difference (P < 0.001).Mean patient CAC scoring was strongly correlated with the number of coronary arteries with significant stenotic lesions (r = 0.910).ConclusionCT CAC scoring is a non-invasive technique which can be used in the evaluation and follow up of CKD patients’ coronary arteries without the use of contrast medium reducing the number of invasive coronary angiography needed.  相似文献   

15.
《Radiography》2016,22(1):97-99
The transient splenial lesion (TSL) of the corpus callosum (CC) is an uncommon radiologic finding incidentally detected on Magnetic Resonance Imaging (MRI).It was first observed in epileptic patients and ever since it has been described in varied neurologic conditions but its etiology is still little known. Slow disappearance of signal abnormalities in the CC mainly occurs after some weeks or months and then TSL carries a good prognosis making unnecessary invasive therapies and procedures. We report a case of an isolated TSL of CC in a patient suffering from psychotic and hormonal disorders, which spontaneously resolved within only one week.  相似文献   

16.
BackgroundScanxiety, the anxiety/stress associated with an imaging test, has never been evaluated in relation to coronary CT angiography (Coronary CTA). As it could impact heart rate and thereby affect image quality of Coronary CTA, we aimed to evaluate the prevalence, severity, and impact of scanxiety on quality and interpretability of Coronary CTA.Methods366 consecutive patients were prospectively presented with a clinical questionnaire comprising two tests to evaluate their scan-related anxiety: the Impact of Event IES-6 (6 questions, final score 0–24) and a visual stress-scale (1 question, score 1–10). Patient demographics, heart rate and final image quality scored by two readers were recorded. Potential independent correlations were sought between IES-6 scanxiety level and image quality, heart rate variability and demographics, using an ordinal logistic regression model.Results344 patients (59.9% men, 57.6 ± 10.7yo) completed the questionnaire. 74.1% (255 patients) reported some scan-related distress, with a mean IES-6 score of 4.1 ± 4.3 (range 0–18). There was no significant difference in terms of age, sex or indications for Coronary CTA between the non-anxious (IES-6 = 0) and the anxious (IES-6>0) patients. There was no significant independent correlation between image quality and IES-6 score (OR = 0.98, p = 0.62), nor between IES-6 score and heart rate variability (effect = −0.005, p = 0.97).ConclusionThe prevalence of scan-related anxiety – aka scanxiety – in Coronary CTA patients is high (74.1%) but does not appear to impact image quality and interpretability.  相似文献   

17.
PurposeTo evaluate the effect of heart rate, heart rate variability on dual-source computed tomography image quality performed without the use of B blockers and to assess diagnostic accuracy of dual-source CT (using adaptive electrocardiographic pulsing) for coronary artery stenosis, by using invasive coronary angiography as the reference standard.Materials and methodsPatients were studied without β-blocker pre-medication. Unenhanced CT and CT coronary angiography with adaptive ECG pulsing were performed using DSCT (DEFINITION, Siemens Medical Solutions, Forchheim, Germany). A contrast-enhanced volume dataset was acquired (two tubes, 120 kV, 400 mAs/rot, collimation 64 × 0.6 mm). Fifty-one patients (11 women, 40 men; mean age, 60.5 years ± 10 [standard deviation]) known to have or suspected of having coronary artery disease underwent dual-source CT and invasive coronary angiography. Accuracy of dual-source CT in depiction or exclusion of significant stenosis (?50%) was evaluated on a per-segment and per-patient basis. Effects of heart rate, heart rate variability were assessed. Patients were divided in three HRF groups: low, intermediate, and high (?65, 66–79, and ?80 beats/min, respectively), and four HRV groups given mean inter beat difference (IBD) during CT coronary angiography: normal, minor, moderate, and severe (IBDs of 0–1, 2–3, 4–10, and >10, respectively). The diagnostic performance was presented as sensitivity, specificity, positive predictive values, and negative predictive values validated against invasive coronary angiography (?50% lumen diameter reduction).ResultsGood image quality was achieved in 98% of patients without the use of B blockers and no significant differences in image quality were found among HRF and HRV groups. Twenty-three patients were examined having a heart rate ?65 beats/min, image quality was sufficient for diagnosis in 281 of 312 coronary segments (92%), whereas in 28 patients with a heart rate <65 beats/min, the image quality was sufficient for diagnosis in 387 of 388 coronary segments (100%). On a per-patient basis, 93% of patients (?65 beats/min) and 100% of patients (<65 beats/min) were considered evaluable. None of these differences were statistically significant. Similarly, no difference in diagnostic accuracy was found in per-vessel and -segment analyses.ConclusionIn 51 patients studied without β-blocker pre-medication, the overall image quality of dual-source CT coronary angiography is sufficient for diagnosis within a wide range of mean heart rates and variability of heart rates. Only heart rates that are both high and variable significantly deteriorate image quality, but the quality remains adequate for diagnosis.  相似文献   

18.
IntroductionCoronary computed tomography angiography (CCTA) has emerged as a useful diagnostic imaging modality in the assessment of coronary artery disease. However, the potential risks due to exposure to ionizing radiation associated with CCTA have raised concerns.ObjectivesCCTA can be done with low dose technique to reduce radiation exposure, without compromise of image quality or diagnostic capabilities.Material and methodsForty patients referred for CCTA were examined with low kV (100 kV for patients ?85–61 kg and 80 kV for patients ?60 kg). The dose length product (DLP) were compared with other group (40 patients) with comparable body weight, scan length and acquisition parameters. The second group was selected from PACS database, for which CCTA was done with standard 120 kV.ResultsThere was considerable reduction of radiation dose about 40% with 100 kV and 60% with 80 kV compared to standard 120 kV CCTA protocols with preserved image quality.ConclusionThe use of lower tube voltage leads to significant reduction in radiation exposure in CCTA. Image quality in non-obese patients is not negatively influenced.  相似文献   

19.
《Radiography》2016,22(4):e228-e232
IntroductionZygomatic fractures can be diagnosed with either computed tomography (CT) or direct digital radiography (DR). The aim of the present study was to assess the effect of CT dose reduction on the preference for facial CT versus DR for accurate diagnosis of isolated zygomatic fractures.Materials and methodsEight zygomatic fractures were inflicted on four human cadavers with a free fall impactor technique. The cadavers were scanned using eight CT protocols, which were identical except for a systematic decrease in radiation dose per protocol, and one DR protocol. Single axial CT images were displayed alongside a DR image of the same fracture creating a total of 64 dual images for comparison. A total of 54 observers, including radiologists, radiographers and oral and maxillofacial surgeons, made a forced choice for either CT or DR.ResultsForty out of 54 observers (74%) preferred CT over DR (all with P < 0.05). Preference for CT was maintained even when radiation dose reduced from 147.4 μSv to 46.4 μSv (DR dose was 6.9 μSv). Only a single out of all raters preferred DR (P = 0.0003). The remaining 13 observers had no significant preference.ConclusionThis study demonstrates that preference for axial CT over DR is not affected by substantial (∼70%) CT dose reduction for the assessment of zygomatico-orbital fractures.  相似文献   

20.
PurposeTo evaluate whether uterine artery embolization (UAE) can reduce the premenstrual symptoms in women undergoing UAE for fibroid tumors or adenomyosis.Materials and MethodsAmong 141 women who underwent UAE for symptomatic fibroid tumors or adenomyosis at a single institution between March 2011 and February 2013, 54 premenstrual symptoms in 39 patients were prospectively analyzed. Premenstrual symptoms were rated by the patient on a scale of 0 to 10, with 0 representing no symptom and 10 representing the baseline severity. The change in premenstrual symptom score was calculated by subtracting the baseline score from the post-UAE score. At 3–6 months after UAE, each woman also completed a symptom severity questionnaire to assess the severity of menstrual bleeding to compare the changes in premenstrual symptoms scores between women with and without menorrhagia.ResultsBack pain, headache, and gastrointestinal symptoms (eg, constipation, indigestion, lower abdominal pain) were significantly improved after UAE (P < .05). Muscle pain, fatigue, nervousness, breast tenderness, and systemic edema were also improved, but not significantly so. The mean premenstrual symptom score change in patients with menorrhagia was significantly greater than in those without menorrhagia (−6.4 vs −3.7; P = .044).There was no correlation between the degree of menorrhagia score change and the degree of premenstrual symptom score change (P = .186).ConclusionsUAE could be a method to alleviate some premenstrual symptoms in patients with uterine fibroid tumors or adenomyosis.  相似文献   

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