Measurement of coronary bifurcation angle with coronary CT angiography: A phantom study

PurposeAccurate determination of the bifurcation angle and correlation with plaque buildup may lead to the prediction of coronary artery disease (CAD). This work evaluates two techniques to measure bifurcation angles in 3D space using coronary computed tomography angiography (CCTA).Materials and MethodsNine phantoms were fabricated with different bifurcation angles ranging from 55.3° to 134.5°. General X-ray and CCTA were employed to acquire 2D and 3D images of the bifurcation phantoms, respectively. Multiplanar reformation (MPR) and volume rendering technique (VRT) were used to measure the bifurcation angle between the left anterior descending (LAD) and left circumflex arteries (LCx). The measured angles were compared with the true values to determine the accuracy of each measurement technique. Inter-observer variability was evaluated. The two techniques were further applied on 50 clinical CCTA cases to verify its clinical value.ResultsIn the phantom setting, the mean absolute differences calculated between the true and measured angles by MPR and VRT were 2.4° ± 2.2° and 3.8° ± 2.9°, respectively. Strong correlation was found between the true and measured bifurcation angles. Furthermore, no significant differences were found between the bifurcation angles measured using either technique. In clinical settings, large difference of 12.0° ± 10.6° was found between the two techniques.ConclusionIn the phantom setting, both techniques demonstrated a significant correlation to the true bifurcation angle. Despite the lack of agreement of the two techniques in the clinical context, our findings in phantoms suggest that MPR should be preferred to VRT for the measurement of coronary bifurcation angle by CCTA.     

Normalized glandular dose coefficients in mammography,digital breast tomosynthesis and dedicated breast CT

PurposeTo provide mean glandular dose (MGD) estimates via Monte Carlo (MC) simulations as a function of the breast models and scan parameters in mammography, digital breast tomosynthesis (DBT) and dedicated breast CT (BCT).MethodsThe MC code was based on GEANT4 toolkit. The simulated compressed breast was either a cylinder with a semi-circular section or ad hoc shaped for oblique view (MLO). In DBT we studied the influence of breast models and exam parameters on the T-factors (i.e. the conversion factor for the calculation of the MGD in DBT from that for a 0-degree projection), and in BCT we investigated the influence on the MGD estimates of the ion chamber volume used for the air kerma measurements.ResultsIn mammography, a model representative of a breast undergoing an MLO view exam did not produce substantial differences (0.4%) in MGD estimates, when compared to a conventional cranio-caudal (CC) view breast model. The beam half value layer did not present a significant influence on T-factors in DBT (<0.8%), while the skin model presented significant influence on MGD estimates (up to 3.3% at 30 degrees scan angle), increasing for larger scan angles. We derived a correction factor for taking into account the different ion chamber volume used in MGD estimates in BCT.ConclusionsA series of MC code modules for MGD estimates in 2D and 3D breast imaging have been developed in order to take into account the most recent advances in breast models.     

Cholesterol esterification and atherogenic index of plasma correlate with lipoprotein size and findings on coronary angiography

We examined the association between rate of cholesterol esterification in plasma depleted of apolipoprotein B-containing lipoproteins (FER(HDL)), atherogenic index of plasma (AIP) [(log (TG/HDL-C)], concentrations, and size of lipoproteins and changes in coronary artery stenosis in participants in the HDL-Atherosclerosis Treatment Study. A total of 160 patients was treated with simvastatin (S), niacin (N), antioxidants (A) and placebo (P) in four regimens. FER(HDL) was measured using a radioassay; the size and concentration of lipoprotein subclasses were determined by nuclear magnetic resonance spectroscopy. The S+N and S+N+A therapy decreased AIP and FER(HDL), reduced total VLDL (mostly the large and medium size particles), decreased total LDL particles (mostly the small size), and increased total HDL particles (mostly the large size). FER(HDL) and AIP correlated negatively with particle sizes of HDL and LDL, positively with VLDL particle size, and closely with each other (r = 0.729). Changes in the proportions of small and large lipoprotein particles, which were reflected by FER(HDL) and AIP, corresponded with findings on coronary angiography. Logistic regression analysis of the changes in the coronary stenosis showed that probability of progression was best explained by FER(HDL) (P = 0.005). FER(HDL) and AIP reflect the actual composition of the lipoprotein spectrum and thus predict both the cardiovascular risk and effectiveness of therapy. AIP is already available for use in clinical practice as it can be readily calculated from the routine lipid profile.     

Dose profiles for lung and breast regions at prospective and retrospective CT coronary angiography using optically stimulated luminescence dosimeters on a 64-detector CT scanner

PurposeThe purpose of our study was to acquire dose profiles at critical organs of lung and breast regions using optically stimulated luminescence (OSL) dosimeters; assess the actual radiation dose delivered at retrospective and prospective computed tomography coronary angiography (CTCA).Materials and methodsUsing a chest CT phantom we applied a prospectively-gated step-and-shoot- and a retrospectively-gated helical mode on a 64-detector row CT scanner. Retrospective scan mode was used with and without electrocardiogram (ECG) based tube current modulation. OSL dosimeters were used to measure dose profiles. In the both scan modes we acquired dose profiles and determined the mean and maximum dose in left lung and in left breast regions.ResultsIn prospective mode, the mean dose was 21.53 mGy in left lung- and 23.59 mGy in left breast region. With respect to the retrospective mode, the mean dose with tube current modulation was 38.63 mGy for left lung- and 46.02 mGy for left breast region, i.e. 0.56 and 0.55 times lower than the mean dose without modulation.ConclusionThe OSL dosimeter is useful for measurement of the actual radiation dose along z-axis at lung and breast regions in the prospective and the retrospective CTCA.     

A surgically confirmed case of breast sparganosis showing characteristic mammography and ultrasonography findings

A case of breast sparganosis was confirmed by surgical excision of a worm (fragmented into 5 pieces) in a 59-year-old Korean woman suffering from a palpable mass in the left breast. Mammography and ultrasonography characteristically revealed the presence of several well-defined, isodense and hypoechoic tubular masses, in the upper quadrant of the left breast, each mass consisting of a continuous cord- or worm-like structure. During surgery, a long segment of an actively moving sparganum of Spirometra sp. and 4 small fragments of the same worm, giving a total length of 20.3 cm, were extracted from the upper outer quadrant of the left breast and the axillary region. The infection source remains unclear, because the patient denied ingesting any snake or frog meat or drinking untreated water.     

Spontaneous intracranial arterial dissection in the young: diagnosis by CT angiography

Background  

Spontaneous carotid artery dissections have been rarely reported in children. Diagnosis has traditionally been confirmed by catheter arteriography. More recently diagnosis has been made by magnetic resonance imaging and magnetic resonance angiography; however the sensitivity of these techniques has yet to be determined. The authors are unaware of reports of carotid dissection confirmed by dynamic computed tomography (computerized tomographic arteriography) in the young.     

无下肢静脉疾病症状者左髂总静脉受压的CTA研究

目的:应用多层螺旋CT血管成像(CTA),探讨无下肢静脉疾病症状人群左髂总静脉受压的发生率及其临床意义.方法:对无下肢静脉疾病症状的130例患者行多层螺旋CT下腹部增强扫描,在右髂总动脉跨越左髂总静脉水平,采用多平面重建方法,显示并测量两侧髂总静脉正交断面上的短径及面积.所有数据经统计学处理.结果:在正交断面上,左髂总静脉短径受压率为33.97%±2.01%,面积受压率为9.98%±1.49%,短径受压率明显高于面积受压率(t=9.586,P=0.000).对左髂总静脉面积受压率进行统计分析,平均受压程度为9.98%,左髂总静脉受压大于25%的患者占16.92%(n=22),左髂总静脉受压大于50%的患者占3.85%(n=5),其中4例为女性.结论:在无下肢静脉疾病症状患者中,左髂总静脉明显受压(受压率>50%)者较少.     

Coronary CT angiography for suspected acute coronary syndrome: sex-associated differences

AimThe optimal diagnostic test in the work-up of suspected acute coronary syndrome (ACS) may differ between men and women. The aim of this study was to compare sex-associated differences between using a diagnostic strategy including early coronary computed tomography angiography (CCTA) and standard of care (SOC).MethodsIn total, 500 patients who presented with symptoms suggestive of ACS at the emergency department were randomised between a diagnostic strategy supplemented with early CCTA and SOC.ResultsWomen were generally older than men (mean ± standard deviation 56 ± 10 vs 53 ± 10 years, p < 0.01) and were less often admitted to hospital (33% vs 44%, p = 0.02). Obstructive coronary artery disease on CCTA (> 50% luminal narrowing) was less frequently seen in women (14% vs 26%, p = 0.02), and ACS was diagnosed less often in women (5% vs 10%, p = 0.03). Women underwent less outpatient testing when early CCTA was used in the emergency department evaluation of suspected ACS (p = 0.008).ConclusionWomen had a lower incidence of obstructive CAD on CCTA and were less often admitted to hospital than men. They were subjected to less outpatient testing when early CCTA was used in the emergency department evaluation of suspected ACS.Supplementary InformationThe online version of this article (10.1007/s12471-021-01607-1) contains supplementary material, which is available to authorized users.     

Selection of optimal cardiac phases for ECG-triggered coronary CT angiography in pediatrics

PurposeThe use of coronary computed tomography angiography (CCTA) in children remains limited by patient’s irradiation, and motion artefacts impairing image quality. Triggering the acquisition at the appropriate moment, and acquiring only necessary components of the cardiac cycle could overcome these limitations. Yet, optimal cardiac intervals to perform CCTA as a function of heart rate (HR) have not yet been addressed in pediatrics.MethodsFifty children with coronary artery anomalies underwent a CCTA on a wide-coverage single-beat CT scanner. Multiple phases from 25% to 85% of the R-R interval were acquired and reconstructed with 10% increments. Two radiologists independently assessed motion artifacts on each cardiac phase using a 4-point semi-quantitative scale.ResultsAt patient level, the best phase for acquisition was found in diastole for patients with HR ≤ 75 bpm and in systole for patients with HR > 85 bpm. At coronary segments and structures level, median optimal phases were reported at 70%, 80%, 47%, 50%, and 54% of the R-R interval for patients with HR ≤ 60, 61–75, 86–100, 101–130, and >130 bpm respectively. For patients with HR between 76 and 85 bpm, no clear trend could be observed. Optimal acquisition durations represented 10% (2 phases), 20% (3 phases), 50% (multiphase), 20% (3 phases), and 10% (2 phases) of the R-R interval for patients with HR ≤ 60, 61–75, 76–100, 101–130, and >130 bpm, respectively.ConclusionsOptimal positioning and duration of CCTA acquisition intervals were investigated as a function of children’s HR, to reduce motion artifacts and patient’s irradiation.     

Multimodality imaging of borderline left main coronary disease using fluoroscopy, IVUS and CT coronary angiography

A borderline left main narrowing was discovered during coronary angiography in a young asymptomatic man with positive stress test. IVUS demonstrated minimal diameter of 2.9 mm and the cross-sectional area was 11.5 mm(2). CTs were performed, and an eccentric calcific plaque was imaged at the ostium of the left main. Based on all three image modalities after discussing the different therapeutic options with the patient he was referred for bypass surgery.     

Incidence of anomalous origin of coronary artery in 1879 Chinese adults on dual-source CT angiography

Background and Objective. Dual-source CT (DSCT) has been used to detect coronary artery anomalies. The purpose of this study was to assess the incidence of anomalous origin of the coronary artery in Chinese adults. Methods. We summarised all patients who underwent DSCT coronary angiography (CTCA) from December 2006 to February 2008, and data of anomalous origin of the coronary artery in Chinese adults were recorded. Results. 1879 patients underwent CTCA during that period; 24 patients with an anomalous origin of the coronary artery were detected, giving an incidence of 1.3%. Fifteen patients had an anomalous origin of the right coronary artery (12 from left coronary sinus, 3 high takeoff), eight patients had an anomalous origin of the left coronary artery (LCA from posterior sinus of Valsalva in three cases, LCX from the right coronary sinus, LCX from RCA, high takeoff, LCA from right coronary sinus, and single coronary artery in one case, respectively), and one patient had an anomalous origin of both coronary arteries (high takeoff). Conclusion. The incidence of anomalous origin of the coronary artery in Chinese adults in this study is 1.3%. DSCT can clearly visualise the anomalous origin and course of the coronary artery and is a useful screening modality. (Neth Heart J 2010;18:466-70.)     

Reciprocal change in ST segment in acute myocardial infarction: correlation with findings on exercise electrocardiography and coronary angiography.

The clinical relevance of reciprocal changes in the ST segment occurring at the time of acute myocardial infarction was studied prospectively in 85 consecutive uncomplicated cases. Reciprocal depression of the ST segment was defined as depression of 1 mm or more in electrocardiogram leads other than those reflecting the infarct. All patients underwent maximal, symptom limited treadmill stress testing two weeks after the infarct and coronary angiography six weeks after infarction. Forty six patients had inferior, 34 anterior, and five true posterior infarction. Of the 51 patients with reciprocal changes, 45 (88%) developed exercise induced ST segment depression in areas remote from the infarction zone. At angiography all 45 patients were shown to have stenoses greater than 70% in at least two major vessels. Four patients had negative exercise electrocardiograms and were sequently shown to have single vessel disease subtending their infarct, and the remaining two patients had a false negative treadmill test result. Of the 27 patients without reciprocal changes, 21 (78%) had negative treadmill stress test results associated with single vessel coronary disease. Five had positive stress test results and multivessel coronary disease, and one had a false negative stress test result. The remaining seven patients had ST segment elevation without Q wave formation in the reciprocal areas and were assessed separately. Of these, six had positive stress test results and multivessel coronary disease and one had a negative stress test result and single vessel coronary disease to the infarct area. Twenty one patients with anterior infarcts (62%) and 27 with inferior infarcts (59%) had reciprocal changes. No differences emerged in the relation between infarct site, reciprocal change, and presence of additional coronary disease. At follow up of the 51 patients with reciprocal changes in the ST segment 36 had become symptomatic, of whom 29 had undergone coronary artery bypass surgery. By contrast, only four of the 27 patients without reciprocal changes in the ST segment had developed symptoms, and two of these had undergone coronary revascularisation. Reciprocal ST segment depression at the time of acute myocardial infarction may identify patients with severe coronary disease who are at risk of subsequent cardiac events and appears to be as reliable as results of early postinfarction treadmill stress testing in predicting the underlying coronary anatomy. When the electrocardiogram does not show reciprocal changes treadmill testing provides valuable additional information.     

体外培养主动脉细胞钙化作用研究

目的：初步探讨主动脉钙化的机制。方法：外殖块法分离培养家兔主动脉平滑肌细胞,进行vonKossa染色以显示钙化,生化法检测细胞内外不溶性钙。放兔法测定培养上清骨钙素的含量。RT-PCR方法检测X型胶原mR-NA的表达。结果：25-羟基胆固醇（A组）和β-甘油磷酸盐（B组）分别培养的传代细胞均可见多个细胞结节,且细胞结节von kossa染色阳性;而对照组（C组）无细胞结节形成,von kossa染色阴性,前二者每孔不溶性钙沉积量,以及培养上清中骨钙素含量明显高于后者,且A、B两组X型胶原mRNA的表达为阳性。结论：25-羟基胆固醇、β-甘油磷酸盐均可促进主动脉中膜细胞发生钙化,主动脉中膜在钙化过程中与成骨细胞相似,骨钙素分泌增多且有X型胶原mRNA的表达。