High-pitch Dual-source Computed Tomography Angiography Research Articles

Sensitivity of High-Pitch Dual-Source Computed Tomography for theDetection of Anomalous Pulmonary Venous Connection in Infants.

To evaluate the sensitivity, specificity, and interobserver reliability of high-pitch dual-source computed tomography angiography (CTA) in the detection of anomalous pulmonary venous connection (APVC) in infants with congenital heart defects and to assess the associated radiation exposure. 78 pulmonary veins in 17 consecutively enrolled patients with congenital heart defects (6 females; 11 males; median age: 6 days; range: 1-299 days) were retrospectively included in this study. All patients underwent high-pitch dual-source CTA of the chest at low tube voltages (70 kV). APVC was evaluated independently by two radiologists. Sensitivity, specificity, positive (PPV) and negative predictive values (NPV), and interobserver agreement were determined. For standard of reference, one additional observer reviewed CT scans, echocardiography reports, clinical reports as well as surgical reports. In cases of disagreement the additional observer made the final decision based on all available information. Detection of APVC with high-pitch dual-source CTA revealed a good sensitivity (91 %) and specificity (99 %), with PPV and NPV of 98 % and 97 %. Interobserver agreement wasalmost perfect (Kappa = 0.84). The median DLP was 3.8mGy*cm (IQR 3.3-4.7 mGy*cm) and the median radiation dose was 0.33 mSv (IQR 0.26-0.39 mSv). High-pitch dual-source CTA in infants with congenital heart defects allows for accurate and reliable assessment of APVC at a low radiation dose. · High-pitch dual-source CTA enables detection of anomalous pulmonary vein connection with high sensitivity in infants.. · Interrater reliability in the detection of anomalous pulmonary vein connection with high-pitch dual-source CTA is almost perfect.. · Radiation dose of high-pitch dual-source CTA in the cardiac examination of infants is low.. · Well L, Weinrich JM, Meyer M et al. Sensitivity of High-Pitch Dual-Source Computed Tomography for the Detection of Anomalous Pulmonary Venous Connection in Infants. Fortschr Röntgenstr 2021; 193: 551 - 558.

Feasibility of Low Volume of High-Concentration Iodinated Contrast Medium With 70 kVp Tube Voltage on High-Pitch Dual-Source Computed Tomography Angiography in Children With Congenital Heart Disease.

The objective of this study was to investigate the feasibility of high-concentration iodinated contrast medium (CM) with 70 kVp tube voltage on high-pitch dual-source computed tomography (DSCT) in children with congenital heart disease (CHD). Fifty-eight CHD patients underwent high-pitch DSCT in 2 protocols: 70 kVp tube voltage, 1.0 mL/kg CM volume, 370 mg I/mL concentration (group A); 80 kVp tube voltage, 1.5 mL/kg CM volume, 350 mg I/mL concentration (group B). The diagnostic accuracy, image quality, iodine delivery rate, iodine dose, and radiation dose were compared. There was no significant difference in the diagnostic accuracy (P > 0.05), image quality (P > 0.05) and iodine delivery rate (P > 0.05) between the 2 groups. The iodine dose (P < 0.05) and radiation dose (P < 0.05) in group A were significantly lower than those in group B. Reduction in iodine dose and radiation exposure can be achieved with 70 kVp high-pitch DSCT by administering a smaller volume of high-concentration CM in children with CHD.

Image Quality of ECG-Triggered High-Pitch, Dual-Source Computed Tomography Angiography for Cardiovascular Assessment in Children

PurposeEvaluate the feasibility and determinants of image quality of ECG-triggered High-Pitch Dual-Source Computed Tomography Angiography (CTA) for cardiovascular assessment in Children. Material and methodsAll children that underwent ECG-triggered High-Pitch Dual-Source CTA between August 2014 and September 2017 were identified. Scanner parameters and patients' information were retrieved. Objective image quality was evaluated measuring the Hounsfield units (HU) and standard deviation of regions of interests in the left ventricle, ascending and descending aorta. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. Qualitative image quality was recorded independently by two pediatric radiologist blinded using a three-point scale: 1 – good image quality, 2 – mild artifacts, 3 – poor image quality. Continuous variables were presented as mean ± standard deviation. The interobserver agreement and non-parametric test were used. Results93 patients (mean age 5.6 ± 7.1 years) were selected. Average cardiovascular attenuation, SNR and CNR were 406.2 ± 146.3 HU, 24.2 ± 16.0 HU and 52.1 ± 38.6 HU, respectively. Average image quality was 1.51 ± 0.48 and the inter-observer agreement was excellent (k = 0.8). Worse subjective quality scores were associated with lower age, height, weight, BSA, lower contrast dose and slower injection rates (p < 0.05). Higher heart rate was associated with high attenuation (p < 0.05), however, SNR and CNR did not show an association with heart rate (p = 0.80). ConclusionsECG-triggered High-Pitch Dual-Source cardiac CTA is feasible and provides good or excellent image quality for the evaluation of cardiovascular diseases in children.

Depiction of the native coronary arteries during ECG-triggered High-Pitch Dual-Source Coronary Computed Tomography Angiography in children: Determinants of image quality

ObjectiveAssess the image quality of ECG-triggered High-Pitch Dual-Source CTA for the evaluation of native coronaries in children. Materials and methodsBetween August 2014 and September 2017, 45 children with morphologically normal cardiac chambers had cardiac prospective ECG-triggered High-Pitch Dual-Source CTA. Two pediatric radiologists blinded to clinical data, independently reviewed each case. The coronary arteries were evaluated using a four-point scale quality score according to the coronary segment. Attenuation, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were measured using values from the air, inter-ventricular septum and ascending aorta at the level of the sinuses of Valsalva. Results225 coronary segments were assessed showed a mean score of 2.40 ± 0.73, 94.2% had diagnostic image quality. The best and worst average quality were seen in segment 5 and 2, respectively. Inter-observer agreement was moderate for all segments except for segment 1, which was excellent. Worse quality scores were significantly associated with younger patients and low body mass index as well as with higher heart rates in all segments. The mean observed heart rate and BSA in patients with diagnostic image quality were below 77 bpm and over 1.4 m2 respectively. There is no significant association between attenuation, SNR and CNR with image quality. ConclusionsProspective ECG-triggered High-Pitch Dual-Source Computed Tomography Angiography achieves consistent and diagnostic image quality for coronary artery assessment at a low effective dose in pediatric patients.

ECG-gated Versus Non-ECG-gated High-pitch Dual-source CT for Whole Body CT Angiography (CTA)

To investigate motion artifacts, image quality, and practical differences in electrocardiographic (ECG)-gated versus non-ECG-gated high-pitch dual-source computed tomography angiography (CTA) of the whole aorta. Two groups, each including 40 patients, underwent either ECG-gated or non-ECG-gated high-pitch dual-source CTA of the whole aorta. The aortic annulus, aortic valve, coronary ostia, and the presence of motion artifacts of the thoracic aorta as well as vascular contrast down to the femoral arteries were independently assessed by two readers. Additional objective parameters including image noise and signal-to-noise ratio were analyzed. Subjective and objective scoring revealed no presence of motional artifacts regardless of whether the ECG-gated or the non-ECG-gated protocol was used (P > 0.1). Image acquisition parameters (examination length, examination duration, radiation dose) were comparable between the two groups without significant differences. The aortic annulus, aortic valve, and coronary ostia were reliably evaluable in all patients. Vascular contrast was rated excellent in both groups. High-pitch dual-source CTA of the whole aorta is a robust and dose-efficient examination strategy for the evaluation of aortic pathologies whether or not ECG gating is used.

High Pitch Dual-Source Whole Aorta CT Angiography in the Detection of Coronary Arteries: A Feasibility Study of Using Iodixanol 270 and 100 kVp with Iterative Reconstruction

Discipline of Medical Imaging, Department of Imaging and App lied Physics, Curtin University, Perth, 6102, AustraliaTo assess the feasibility of detecting coronary arteries through high-pitch dual-source computed tomography(DSCT) thoracoabdominal angiography when using low-concentration contrast medium, low tube voltage, anditerative reconstruction. One hundred patients undergoing DSCT angiography with high-pitch data acquisitionmode were prospectively enrolled in this study. F ifty patients were assigned to receive Iodixanol 270 andscanned using the low tube voltage (100 kVp) technique and iterative reconstruction, while another Þfty patientswere assigned to Iopamidol 370 and scanned under the conventional tube voltage (120 kVp) with the imageswere reconstructed with Þltered back projection. Bo th subjective and objective assessment of image qualitywas performed and compared between the two groups by measuring the image noise, signal-to-noise ratio andcontrast-to-noise ratio in the coronary arteries. Diagnostic images were obtained for 1267 of the 1325 segments(95.6%). No signiÞcant differences in image quality wer e found between patients given Iodixanol 270 and Iopami-dol 370. The effective dose and contrast medium dose were 4.4 ± 0.5 mSv and 6.7 ± 0.6 mSv, 20.36 ± 2.65 gand 28 ± 1.98 g, corresponding to the Iodixanol 270 and Iopam idol 370 groups, respectively, with 34.3% dosereduction achieved in the low contrast medium Iodix anol 270 group. High-pitch DSCT angiography of the tho-racoabdominal aorta utilizing low iodine concentration contrast medium (Iodixanol 270), low tube voltage, anditerative reconstruction is a feasible protocol with signiÞcant reduction in r adiation dose and contrast medium,without compromising image quality.

Evaluation of high-pitch dual-source CT angiography for evaluation of coronary and carotid-cerebrovascular arteries

ObjectivesTo explore the feasibility and diagnostic accuracy of a combined one-step high-pitch dual-source computed tomography angiography (CTA) technique for evaluation of coronary and carotid-cerebrovascular arteries. Materials and methods85 symptomatic patients suspected of coronary artery and cerebrovascular disease referred for simultaneous coronary and carotid-cerebrovascular CTA were included. Additional invasive angiography of the coronary and cerebral arteries was performed within 30 days in 23 and 13 patients, respectively. The objective parameters of image quality, the mean CT attenuations, image noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were evaluated. The subjective image quality of vessels was also assessed by 2 independent radiologists blinded to the patients’ medical history and scan protocols. The diagnostic performance of CTA including sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for the detection or exclusion of significant artery stenosis was calculated using the chi-squared test of contingency and correlated with the results of invasive angiography representing the standard of reference. ResultsImage quality was rated excellent (score 1) in 95.3% (1074/1127), good (score 2) in 3.3% (37/1127), adequate (score 3) in 1.0% (11/1127), and non-diagnostic (score 4) in 0.4% (5/1127) of coronary segments. Image quality of carotid and cerebral vessels was rated mostly excellent (score 1, 95.12% [78/82]; score 2, 3.66% [3/82]; score 3, 1.22% [1/82]). The sensitivity, specificity, PPV and NPV for the detection of coronary stenosis were 92.2% (81.1–97.7%), 95.2% (91.7–97.5%), 79.6% (67.1–89.1%) and 98.3% (95.8–99.5%), respectively. For the detection of carotid and cerebral artery stenosis, CTA demonstrated a sensitivity of 92.8% (80.5–98.4%), a specificity of 93.5% (88.3–96.8%), a PPV of 79.6% (65.6–89.7%) and a NPV of 97.9% (94.1–99.5%). The effective radiation dose was 1.42±0.44mSv (range, 0.88–3.35mSv). ConclusionDual-source CT with a one-step high-pitch scan protocol for combined coronary and carotid-cerebrovascular CTA provides good image quality and a high diagnostic accuracy for the simultaneous evaluation of coronary, carotid and cerebral artery stenosis and may be a useful examination with relatively low radiation exposure in patients with suspected coronary and carotid-cerebrovascular disease.

Accuracy, Image Quality, and Radiation Dose of Prospectively ECG-Triggered High-Pitch Dual-Source CT Angiography in Infants and Children with Complex Coarctation of the Aorta

To evaluate the diagnostic accuracy, image quality, and radiation dose of prospective electrocardiogram (ECG)-triggered high-pitch dual-source computed tomography (DSCT) in infants and young children with complex coarctation of the aorta (CoA). Forty pediatric patients aged < 4 years with suspected CoA underwent prospective ECG-triggered high-pitch DSCT angiography and transthoracic echocardiography (TTE). Surgery and/or conventional cardiac angiography (CCA) were performed in all patients. The diagnostic accuracy of DSCT angiography and TTE was compared to the surgical and/or CCA findings. The causes of misdiagnosis and miss were analyzed, and the advantages and limitation of both imaging modalities were evaluated. Image quality of DSCT was evaluated, and effective radiation dose was calculated. The sensitivity, specificity, positive predictive value, negative predictive value, and overall diagnostic accuracy of DSCT in evaluation of complex CoA were 92.37%, 98.51%, 97.32%, 93.57%, and 96.25%, respectively. There was a significant difference in the accuracy between DSCT and TTE (χ² = 9.9, P＜.05). For a total of 80 extracardiac anomalies, the sensitivity (98.8%, 79/80) of DSCT was greater than that of TTE (62.5%; 50 of 80). On the contrary, for 38 cardiac anomalies, the sensitivity (78.9%, 30 of 38) of DSCT was lesser than that of TTE (100%; 38 of 38). The mean score of image quality was 4.27 ± 0.73. The mean effective radiation dose was 0.20 ± 0.09 mSv. Prospective ECG-triggered high-pitch DSCT may be a clinical feasible modality in the evaluation of pediatric patients with complex CoA, providing adequate image quality, high diagnostic accuracy, and low radiation dose.

Benefits of High-Pitch 128-Slice Dual-Source Computed Tomography for Planning of Transcatheter Aortic Valve Implantation

Transcatheter aortic valve implantation (TAVI) has emerged as an alternative treatment for high-risk and inoperable patients. Advanced multimodality imaging, including computed tomography (CT), plays a key role for optimized planning of TAVI. Forty-nine patients (25 women; age, 82.3±8.8 year) with severe aortic stenosis scheduled for TAVI were examined with 128-slice high-pitch dual-source prospective aortoiliac CT angiography (CTA). The 3-coronary-sinus-alignment (3-CSA) plane, comprising left and right anterior oblique and craniocaudal projection, was defined from three-dimensional volume-rendered technique data sets and compared with the intraoperative angiographic plane (deployment plane) used for device implantation. A tolerance level of ±5-degree deviation was acceptable. Volume of intraoperative iodine contrast agent was compared before and after the implementation of the 3-CSA plane estimation by CT. All 49 patients underwent TAVI, during which 6 CoreValves (Medtronic, Minneapolis, MN) and 43 Sapien valves (Edwards Lifesciences, Irvine, CA) were successfully implanted using transapical (n=29), transfemoral (n=17), and transaxillary access (n=4). No severe complications occurred. In 47 patients (96%), CTA correctly predicted the 3-CSA plane used for device implantation. Mean left anterior oblique by CTA was 5.3±6.5 degrees and craniocaudal was -1.3±10.1 degrees. Mean left anterior oblique deviation between CTA and the intraoperative projection was 2.1±2.7 degrees and craniocaudal was 1.7±3.0 degrees. Ostium heights of the right and left coronary arteries were 12±1.9 and 12.9±3.3 mm. No over-stenting occurred in left coronary artery ostia of 8 mm or more. Contrast volume was reduced from 81.8±25.6 to 59.4±40.2 mL (p=0.05) when using 3-CSA plane estimation by CT for final prosthesis implantation plane. Aortoiliac high-pitch 128-slice dual-source CT contributes to TAVI planning, including reliable prediction of the 3-CSA valve deployment plane, which saves contrast volume during the procedure and may facilitate correct valve placement.

Thoraco-abdominal high-pitch dual-source CT angiography: Experimental evaluation of injection protocols with an anatomical human vascular phantom

ObjectiveTo experimentally evaluate three different contrast injection protocols at thoraco-abdominal high-pitch dual-source computed tomography angiography (CTA), with regard to level and homogeneity of vascular enhancement at different cardiac outputs. Materials and methodsA uniphasic, a biphasic as well as an individually tailored contrast protocol were tested using a human vascular phantom. Each protocol was scanned at 5 different cardiac outputs (3–5L/min, steps of 0.5L/min) using an extracorporeal cardiac pump. Vascular enhancement of the thoraco-abdominal aorta was measured every 5cm. Overall mean enhancement of each protocol and mean enhancement for each cardiac output within each protocol were calculated. Enhancement homogeneity along the z-axis was evaluated for each cardiac output and protocol. ResultsOverall mean enhancement was significantly higher in the uniphasic than in the other two protocols (all p<.05), whereas the difference between the biphasic and tailored protocol was not significant (p=.76). Mean enhancement among each of the 5 cardiac outputs within each protocol was significantly different (all p<.05). Only within the tailored protocol mean enhancement differed not significantly at cardiac outputs of 3.5L/min vs. 5L/min (484±25HU vs. 476±19HU, p=.14) and 4 vs. 5L/min (443±49HU vs. 476±19HU, p=.05). Both, uniphasic and tailored protocol yielded homogenous enhancement at all cardiac outputs, whereas the biphasic protocol failed to achieve homogenous enhancement. ConclusionThis phantom study suggests that diagnostic and homogenous enhancement at thoraco-abdominal high-pitch dual-source CTA is feasible with either a uniphasic or an individually tailored contrast protocol.

High-Pitch Thoracic CT With Simultaneous Assessment of Coronary Arteries: Effect of Heart Rate and Heart Rate Variability on Image Quality and Diagnostic Accuracy

The aim of this study was to evaluate the mean heart rate and heart rate variability (HRV) required for diagnostic imaging of the coronary arteries simultaneously with thoracic computed tomography for noncardiac purposes, applying a high-pitch spiral image acquisition protocol for computed tomography angiography (CTA) using a dual-source system. For the primary prevention of coronary heart disease, screening methods to identify currently asymptomatic people who are at high risk for developing coronary heart disease are essential. Coronary CTA can rule out coronary artery stenoses with high negative predictive value. High-pitch thoracic computed tomography was performed in 111 consecutive patients (mean age 60.2 ± 11.5 years; range 37 to 81 years) using a dual-source system (2 × 128 0.6-mm sections, 38.4-mm collimation width, 0.28-s rotation time). Data acquisition was prospectively electrocardiographically triggered at 60% of the R-R interval using a pitch of 3.2. Image quality was evaluated using a 3-point scale (1=excellent, 2=moderate, 3=poor). Close interobserver agreement for image quality scores of 1,998 evaluated coronary segments was found (κ=0.93). Image quality was of diagnostic value in 828 of 1,739 segments (47.6%). In 29 of 111 patients (26%), diagnostic image quality was observed for all segments. Average heart rate and HRV were significantly (p<0.001) higher in patients with at least 1 nondiagnostic coronary segment compared with those without. All patients with mean heart rates <64 beats/min and HRV <13 beats/min had diagnostic image quality in all coronary segments. Effective radiation dose for thoracic CTA was 1.9 ± 0.66 mSv. The mean scan time was 0.9 ± 0.1 s. Simultaneous evaluation of coronary arteries in high-pitch dual-source CTA of the thorax for noncardiac purposes is consistently diagnostic in patients with low heart rates and HRV, whereas most patients not receiving beta-blockers had at least 1 segment that was not diagnostic because of heart rate and HRV. Beta blockers are recommended if there are no contraindications and coronary interpretation is anticipated.

High-pitch dual-source CT angiography of the aortic valve-aortic root complex without ECG-synchronization

To compare image quality and radiation dose of high-pitch computed tomography angiography(CTA) of the aortic valve-aortic root complex with and without prospective ECG-gating compared to a retrospectively ECG-gated standard-pitch acquisition. 120 patients (mean age 68±13 years) were examined using a 128-slice dual-source CT system using prospectively ECG-gated high-pitch (group A; n=40), non-ECG-gated high-pitch (group B; n=40) or retrospectively ECG-gated standard-pitch (C; n=40) acquisition techniques. Image quality of the aortic root, valve and ascending aorta including the coronary ostia was assessed by two independent readers. Image noise was measured, radiation dose estimates were calculated. Interobserver agreement was good(κ=0.64-0.78). Image quality was diagnostic in 38/40 patients (group A), 37/40(B) and 38/40(C) with no significant difference in number of patients with diagnostic image quality among all groups (p=0.56). Significantly more patients showed excellent image quality in group A compared to groups B and C (each, p<0.01). Average image noise was significantly different between all groups (p<0.05). Mean radiation dose estimates in groups A and B (each; 2.4±0.3 mSv) were significantly lower compared to group C (17.5±4.4 mSv; p<0.01). High-pitch dual-source CTA provides diagnostic image quality of the aortic valve-aortic root complex even without ECG-gating at 86% less radiation dose when compared to a standard-pitch ECG-gated acquisition.