3D Angiography Research Articles

Abstract TP86: Predicting Aneurysm Occlusion After Flow Diversion

Introduction: Predicting the course of aneurysms after treatment with flow diverters is important to prognosticate long term outcomes and optimize interventions. Hypothesis: Aneurysm occlusion after flow diversion can be predicted using post-treatment flow information. Methods: Flows in experimental aneurysms in rabbits (n=15) and clinical cases (n=23) were evaluated with computational fluid dynamics. Subject-specific models were created from 3D angiographies. Flow conditions were measured with ultrasound in the rabbits, and derived from measurements in normal subjects in the clinical cases. Models of the devices were virtually deployed into the anatomical models. Experimental aneurysms were assigned to either a “complete” occlusion group if completely occluded at 4 weeks follow up, or to an “incomplete” occlusion group if still open at 8 weeks. Similarly, clinical cases were classified as “complete” occlusions if completely occluded at 3 months, or as “incomplete” occlusions if still patent at 6 months. Flow variables were then statistically compared between these groups for both the experimental and clinical series, and the predictive power of different variables to discriminate between aneurysms in each group was assessed by calculating the area under the receiving operating characteristics curves. Results: In the clinical (experimental) series, the aneurysm inflow rate was 4.02 (3.29) times larger in the incomplete occlusion group than in the completely occluded group, p=0.0210 (0.0239). Similarly, the mean aneurysm velocity was 2.75 (2.29) times larger, p=0.0044 (0.0582), and the shear rate was 1.57 (1.78) times larger, p=0.0210 (0.0722). Inflow rate could discriminate complete and incomplete occlusions with a 77% (90%) accuracy in the clinical (experimental) series. Similarly, mean velocity had a predictive power of 84% (83%) and shear rate of 76% (76%) in the clinical and experimental series. Conclusions: Flow conditions created immediately after treatment, in particular aneurysm inflow rate and mean aneurysm velocity, can prognosticate the future occlusion of aneurysms treated with flow diverters.

7T MRI in focal epilepsy with unrevealing conventional field strength imaging.

To assess the diagnostic yield of 7T magnetic resonance imaging (MRI) in detecting and characterizing structural lesions in patients with intractable focal epilepsy and unrevealing conventional (1.5 or 3T) MRI. We conducted an observational clinical imaging study on 21 patients (17 adults and 4 children) with intractable focal epilepsy, exhibiting clinical and electroencephalographic features consistent with a single seizure-onset zone (SOZ) and unrevealing conventional MRI. Patients were enrolled at two tertiary epilepsy surgery centers and imaged at 7T, including whole brain (three-dimensional [3D] T1 -weighted [T1W] fast-spoiled gradient echo (FSPGR), 3D susceptibility-weighted angiography [SWAN], 3D fluid-attenuated inversion recovery [FLAIR]) and targeted imaging (2D T2*-weighted dual-echo gradient-recalled echo [GRE] and 2D gray-white matter tissue border enhancement [TBE] fast spin echo inversion recovery [FSE-IR]). MRI studies at 1.5 or 3T deemed unrevealing at the referral center were reviewed by three experts in epilepsy imaging. Reviewers were provided information regarding the suspected localization of the SOZ. The same team subsequently reviewed 7T images. Agreement in imaging interpretation was reached through consensus-based discussions based on visual identification of structural abnormalities and their likely correlation with clinical and electrographic data. 7T MRI revealed structural lesions in 6 (29%) of 21 patients. The diagnostic gain in detection was obtained using GRE and FLAIR images. Four of the six patients with abnormal 7T underwent epilepsy surgery. Histopathology revealed focal cortical dysplasia (FCD) in all. In the remaining 15 patients (71%), 7T MRI remained unrevealing; 4 of the patients underwent epilepsy surgery and histopathologic evaluation revealed gliosis. 7T MRI improves detection of epileptogenic FCD that is not visible at conventional field strengths. A dedicated protocol including whole brain FLAIR and GRE images at 7T targeted at the suspected SOZ increases the diagnostic yield.

Effects of Non-Newtonian Viscosity on the Hemodynamics of Cerebral Aneurysms

The purpose of this study is to present a comparative study between Newtonian and non-Newtonian blood viscosity models for simulating the hemodynamic wall shear stress (WSS) of cerebral aneurysms. The non-Newtonian blood viscosity was modeled using the Carreau-Yasuda nonlinear model. Two realistic cerebral aneurysm models, derived from 3D angiography imaging, were studied and simulated via computational fluid dynamics solver based on finite volume method, with a pulsating sinusoidal waveform boundary conditions. The maximum wall shear stresses were found at the aneurysm’s neck and apex, the inlet arteriole recorded an average wall shear stress and as for the blebs and tips the wall shear stress values were remarkably low. The comparison indicated that non-Newtonian blood viscosity model predicted a lower range of WSS than of the Newtonian model, which provides more accuracy for simulating aneurysm hemodynamics.

Cerebal sulci and gyri are intrinsic landmarks for brain navigation in individual subjects: an instrument to assist neurosurgeons in preserving cognitive function in brain tumour surgery (Commentary on Zlatkina etal.).

Cerebal sulci and gyri are intrinsic landmarks for brain navigation in individual subjects: an instrument to assist neurosurgeons in preserving cognitive function in brain tumour surgery (Commentary on Zlatkina etal.).

Low-dose 2D X-ray angiography enhancement using 2-axis PCA for the preservation of blood-vessel region and noise minimization

Enhancing 2D angiography while maintaining a low radiation dose has become an important research topic. However, it is difficult to enhance images while preserving vessel-structure details because X-ray noise and contrast blood vessels in 2D angiography have similar intensity distributions, which can lead to ambiguous images of vessel structures. In this paper, we propose a novel and fast vessel-enhancement method for 2D angiography. We apply filtering in the principal component analysis domain for vessel regions and background regions separately, using assumptions based on energy compaction. First, we identify an approximate vessel region using a Hessian-based method. Vessel and non-vessel regions are then represented sparsely by calculating their optimal bases separately. This is achieved by identifying periodic motion in the vessel region caused by the flow of the contrast medium through the blood vessels when viewed on the time axis. Finally, we obtain noise-free images by removing noise in the new coordinate domain for the optimal bases. Our method was validated for an X-ray system, using 10 low-dose sets for training and 20 low-dose sets for testing. The results were compared with those for a high-dose dataset with respect to noise-free images. The average enhancement rate was 93.11±0.71%. The average processing time for enhancing video comprising 50–70 frames was 0.80±0.35s, which is much faster than the previously proposed technique. Our method is applicable to 2D angiography procedures such as catheterization, which requires rapid and natural vessel enhancement.

3D bone subtraction CT angiography for the evaluation of intracranial aneurysms: a comparison study with 2D bone subtraction CT angiography and conventional non-subtracted CT angiography.

Bone subtraction computed tomography angiography (BSCTA) is better able to facilitate the detection of intracranial aneurysms adjacent to bone structures compared to conventional non-subtracted CTA (CNSCTA). However, the comparison of the diagnostic accuracy of three-dimensional (3D) and two-dimensional (2D) BSCTA and conventional CTA in evaluating intracranial aneurysms remains unclear. To evaluate whether 3D BSCTA has a superior diagnostic accuracy to those of 2D BSCTA and CNSCTA in a single center with the same instrument. Sixty-three patients received 3D BSCTA, 2D BSCTA, and NSCTA for the detection and treatment planning of suspected intracranial aneurysms. The angiography readouts were reviewed by two independent radiologists. The sensitivity of CTA in detecting aneurysm was analyzed on a per-aneurysm and per-patient basis, using 3D digital subtraction angiography (DSA) and surgical findings as the gold standard. The potential of endovascular treatment or surgical clipping was also assessed based on information provided by the CTA. A total of 66 aneurysms were detected in 54 patients. The overall sensitivity, specificity, positive, and negative predictive values of 3D BSCTA were all 100%, and these values for 2D BSCTA were 98.1%, 100%, 100%, and 90%, respectively. The total sensitivity, specificity, positive, and negative predictive values of CNSCTA were 94.4%, 100%, 100%, and 75%, respectively. Finally, 100%, 98.1%, and 85.2% patients received appropriate treatment decisions after 3D BSCTA, 2D BSCTA, and CNSCTA imaging, respectively. 3D BSCTA has a higher sensitivity for the detection of small aneurysms and aneurysms adjacent to bone compared to 2D BSCTA or CNSCTA, which were still able to obtain sufficient information for the detection of intracranial aneurysms and therapeutic decision-making.

Artery of the Superior Orbital Fissure: An Undescribed Branch from the Pterygopalatine Segment of the Maxillary Artery to the Orbital Apex Connecting with the Anteromedial Branch of the Inferolateral Trunk.

Some branches of the internal maxillary artery have anastomoses with the inferolateral trunk that are important as intracranial-extracranial collateral pathways and as dangerous anastomoses for transarterial embolization of these branches. We present here an undescribed branch potentially anastomosing with the anteromedial branch of the inferolateral trunk, which is provisionally named the artery of the superior orbital fissure, defined as an arterial branch from the pterygopalatine segment of the maxillary artery to the orbital apex at the superior orbital fissure. Two neuroradiologists reviewed 3D and MPR images of the external and/or common carotid artery with particular interest paid to the artery of the superior orbital fissure in 54 patients who underwent 3D angiography with a field of view covering the pterygopalatine fossa and the cavernous sinus. The underlying diseases in these patients were 17 parasellar hypervascular lesions (including 13 cavernous sinus dural arteriovenous fistulas and 4 meningiomas), 18 internal carotid artery stenoses/occlusions, and 19 other diseases. The artery of the superior orbital fissure was identified in 20 of 54 patients; it arose at the pterygopalatine segment of the maxillary artery, either singly or from a common trunk with the artery of the foramen rotundum, and ran upward to reach the superior orbital fissure. It anastomosed with the anteromedial branch of the inferolateral trunk at the superior orbital fissure with blood flow toward the cavernous sinus (n = 14) and/or the ophthalmic artery (n = 2). It was more prominent in parasellar hypervascular lesions and internal carotid artery stenoses/occlusions than in other diseases. The artery of the superior orbital fissure, a remnant of the anastomotic artery, was often identified, especially in patients with parasellar hypervascular lesions.

Impact of Side Branch Modeling on Computation of Endothelial Shear Stress in Coronary Artery Disease: Coronary Tree Reconstruction by Fusion of 3D Angiography and OCT

BackgroundComputational fluid dynamics allow virtual evaluation of coronary physiology and shear stress (SS). Most studies hitherto assumed the vessel as a single conduit without accounting for the flow through side branches. ObjectivesThis study sought to develop a new approach to reconstruct coronary geometry that also computes outgoing flow through side branches in hemodynamic and biomechanical calculations, using fusion of optical coherence tomography (OCT) and 3-dimensional (3D) angiography. MethodsTwenty-one patients enrolled in the DOCTOR (Does Optical Coherence Tomography Optimize Revascularization) fusion study underwent OCT and 3D-angiography of the target vessel (9 left anterior descending, 2 left circumflex, 10 right coronary artery). Coronary 3D reconstruction was performed by fusion of OCT and angiography, creating a true anatomical tree model (TM) including the side branches, and a traditional single-conduit model (SCM) disregarding the side branches. ResultsThe distal coronary pressure to aortic pressure (Pd/Pa) ratio was significantly higher in TMs than in SCMs (0.904 vs. 0.842; p < 0.0001). Agreement between TM and SCM in identifying patients with a Pd/Pa ratio ≤0.80 under basal flow conditions was only k = 0.417 (p = 0.019). Average SS was 4.64 Pascal lower in TMs than in SCMs (p < 0.0001), with marked differences in the point-per-point comparison, ranging from -60.71 to 7.47 Pascal. ConclusionsTrue anatomical TMs that take into account the flow through side branches are feasible for accurate hemodynamic and biomechanical calculations. Traditional SCMs underestimate Pd/Pa and are inaccurate for regional SS estimation. Implementation of TMs might improve the accuracy of SS and virtual fractional flow reserve calculations, thus improving the consistency of biomechanical studies.

Three-Dimensional Optoacoustic and Laser-Induced Ultrasound Tomography System for Preclinical Research in Mice: Design and Phantom Validation.

In this work, we introduce a novel three-dimensional imaging system for in vivo high-resolution anatomical and functional whole-body visualization of small animal models developed for preclinical and other type of biomedical research. The system (LOUIS-3DM) combines a multiwavelength optoacoustic tomography (OAT) and laser-induced ultrasound tomography (LUT) to obtain coregistered maps of tissue optical absorption and speed of sound, displayed within the skin outline of the studied animal. The most promising applications of the LOUIS-3DM include 3D angiography, cancer research, and longitudinal studies of biological distributions of optoacoustic contrast agents.

Vascular changes responsible for the reduced effectiveness of obliteration of uterine arteries in women with advanced cervical cancer.

IntroductionHaemorrhages from the genital tract remain a major threat to the life of patients with advanced cervical cancer. It is possible to achieve haemostasis by both surgical techniques and the procedure of endovascular uterine artery embolization. However, in some women with loco-regionally advanced cervical cancer the obliteration of the uterine arteries is not effective.AimEvaluation of morphological changes in uterine arteries in patients with advanced cervical cancer and comparison of their changes with the achieved haemostatic effect of obliteration.Material and methodsThe prospective study included a group of 8 women with cervical cancer at a clinical stage of IIB to IIIC according to the FIGO classification. 3D quantitative coronary angiography (QCA) was performed before uterine embolization. The haemostatic effect of uterine artery embolization was compared with observed vascular changes.ResultsMean uterine artery length in patients who achieved complete hemostasis: 39.5 mm – right uterine artery; 38.7 mm – left uterine artery. Mean uterine artery length in patients who achieved partial satisfactory haemostasis: 32 mm – right uterine artery; 30.5 mm – left uterine artery. Mean uterine artery length in patients who achieved unsatisfactory haemostasis: 10.5 mm – right uterine artery; 19 mm – left uterine artery.ConclusionsShortening of uterine arteries worsens prognosis of the haemostatic effect of their obliteration in patients with advanced cervical cancer.

Usefulness of operative planning based on 3-dimensional CT cholangiography for biliary malignancies

The complexity of hepatic hilar anatomy is an obstacle to precise diagnosis of tumor spread and appropriate operative planning for biliary malignancies. Three-dimensional (3D) cholangiography and angiography may overcome this obstacle and facilitate curative resection. The objective of this study was to evaluate the impact of 3D CT cholangiography on operative planning and outcomes of biliary malignancies. From 2009 to 2014, 3DCT cholangiography was performed on 49 patients with biliary malignancies requiring major hepatic resection and extrahepatic bile duct resection. The 3D cholangiogram was merged with 3D angiography and portography to create an all-in-one 3D image of the hepatic hilum. The cutting line of the bile duct and the type of liver resection were determined based on the spatial relationship between tumor spread and the landmark vessels. The necessity of vascular reconstruction was also evaluated. Preoperative imaging and operative findings were compared. Operative curability was compared with that of the historical cohort before the introduction of 3D cholangiography. Histologic examination of the bile duct stump showed a negative margin in 39 (80%), carcinoma in situ in 7 (14%), and invasive cancer (IC) in 3 patients (6%) on the first cutting. The IC-free rate (94%) on the first cutting was superior to that in the historical cohort (80%; P = .02). The necessity for portal and arterial reconstruction was predicted with 98 and 94% accuracy, respectively. We found 3D cholangiography to provide accurate information about hilar anatomy and plays a role in facilitating adequate operative planning.

Characterization of Craniocervical Artery Dissection by Simultaneous MR Noncontrast Angiography and Intraplaque Hemorrhage Imaging at 3T.

Craniocervical artery dissection is the most common cause of ischemic stroke identified in young adults. For the diagnosis of craniocervical artery dissection, multisequence MR imaging is recommended but is time-consuming. Recently, investigators proposed a simultaneous noncontrast angiography and intraplaque hemorrhage imaging technique allowing simultaneous noncontrast MRA and vessel wall imaging in a single scan. This study sought to investigate the feasibility of 3D simultaneous noncontrast angiography and intraplaque hemorrhage MR imaging in the characterization of craniocervical artery dissection. Twenty-four symptomatic patients (mean age, 45.0 ± 16.1 years; 21 men) with suspected craniocervical artery dissection were recruited. The 3D simultaneous noncontrast angiography and intraplaque hemorrhage 3D TOF MRA and black-blood imaging sequences were performed on a 3T MR imaging scanner. The agreement between simultaneous noncontrast angiography and intraplaque hemorrhage imaging and multisequence MR imaging in evaluating arterial dissection was determined. Dissection was found to involve 1 artery in 22 patients and 2 arteries in 2 patients. The intramural hematoma and luminal occlusion were detected in 19 (79.2%) and 11 (45.8%) patients, respectively. In measuring stenosis, the Cohen κ value between 3D TOF MRA and simultaneous noncontrast angiography and intraplaque hemorrhage imaging was 0.82 (P < .001). All intramural hematomas on multisequence imaging were successfully identified by simultaneous noncontrast angiography and intraplaque hemorrhage imaging. 3D simultaneous noncontrast angiography and intraplaque hemorrhage imaging showed excellent agreement with multisequence MR imaging in evaluating luminal stenosis and intramural hematoma in patients with craniocervical artery dissection. The simultaneous noncontrast angiography and intraplaque hemorrhage imaging saved nearly 50% of scanning time compared with multisequence MR imaging. Our findings suggest that 3D simultaneous noncontrast angiography and intraplaque hemorrhage imaging might be an alternative, time-efficient diagnostic tool for craniocervical artery dissection.

Continuous roadmapping in liver TACE procedures using 2D-3D catheter-based registration.

PurposeFusion of pre/perioperative images and intra-operative images may add relevant information during image-guided procedures. In abdominal procedures, respiratory motion changes the position of organs, and thus accurate image guidance requires a continuous update of the spatial alignment of the (pre/perioperative) information with the organ position during the intervention.MethodsIn this paper, we propose a method to register in real time perioperative 3D rotational angiography images (3DRA) to intra-operative single-plane 2D fluoroscopic images for improved guidance in TACE interventions. The method uses the shape of 3D vessels extracted from the 3DRA and the 2D catheter shape extracted from fluoroscopy. First, the appropriate 3D vessel is selected from the complete vascular tree using a shape similarity metric. Subsequently, the catheter is registered to this vessel, and the 3DRA is visualized based on the registration results. The method is evaluated on simulated data and clinical data.ResultsThe first selected vessel, ranked with the shape similarity metric, is used more than 39 % in the final registration and the second more than 21 %. The median of the closest corresponding points distance between 2D angiography vessels and projected 3D vessels is 4.7–5.4 mm when using the brute force optimizer and 5.2–6.6 mm when using the Powell optimizer.ConclusionWe present a catheter-based registration method to continuously fuse a 3DRA roadmap arterial tree onto 2D fluoroscopic images with an efficient shape similarity.

Definitions and classifications of bifurcation lesions and treatment.

This article introduces the new terminology proposed by the European Bifurcation Club in order to simplify the identification, description, localisation and measurement of coronary bifurcation lesions as well as the selection of appropriate treatment strategies. A bifurcation lesion is a coronary artery narrowing occurring adjacent to, and/or involving, the origin of a significant side branch that you do not want to lose. The very simple Medina classification is intended for exchange and clinical research purposes. It is combined with a clear side branch definition and is associated with multiple measurement and imaging modalities, which take into account the complexity of lesions and treatments. Dedicated angiography as well as 3D angiography and multislice computed tomography are absolutely necessary for measurement of the bifurcation angles. The MADS (Main, Across, Distal, Side) classification is based on the final position of the stents in the bifurcation and on the order in which stents are implanted according to a strategy reflecting lesion and technique complexity. Although this classification still seems exhaustive, it does not involve the numerous guide and balloon manoeuvres, which would require a thorough a posteriori electronic classification of all inherent specific technical details.

Pancreaticoduodenectomy in the presence of a common hepatic artery originating from the superior mesenteric artery. Technical implications

Pancreaticoduodenectomy (PD) is considered a technically demanding task. Anatomic variations in duodenopancreatic vascularization [celiac axis and the superior mesenteric artery (SMA)] may carry a risk of potentially life-threatening vascular injury. We retrospectively report a modified PD technique performed in two patients presenting with a Common Hepatic Artery (CHA) originating from SMA. The CHA anatomical pattern was known prior surgical procedure. The main modification consisted in cutting pancreas prior dividing the CHA and the gastroduodenal artery. No intraoperative incident was reported. Perioperative outcomes were unremarkable, no vascular injury or hepatic ischemia was reported. Surgeons planning a PD must analyze in depth imaging (CT-scan with 3D angiography) and try to find these patterns. Furthermore, some rare arterial variations may be met and change typical surgical plan. Knowing prior procedure the arterial pattern and keeping in mind expendable or vital vessels allow to accomplish unusual but effective operations.

3D time-resolved vessel-selective angiography based on pseudo-continuous arterial spin labeling

Angiographic imaging is an important diagnostic tool for the assessment of the intracranial arterial status. Using arterial spin labeling (ASL) techniques, it is possible to visualize the arteries without the administration of exogenous contrast agents. Moreover, modifications of the labeling method allow for the visualization of single arterial trees. In this study, an approach is presented for time-resolved MR angiography based on superselective ASL and keyhole accelerated image acquisition in order to selectively visualize individual cerebral arteries in a clinically acceptable scan time. Keyhole percentage as well as the flip angle of the acquisition sequence was optimized in numerical simulations. Subsequently, the method was validated in healthy volunteers. As a result, image acquisition in 5 minutes with a temporal resolution of 100 ms and spatial resolution below 1 mm was achieved.

Three-dimensional rotational angiography in the assessment of vascular and airway compression in children after a cavopulmonary anastomosis.

The aim of the study was to examine the role of three-dimensional rotational angiography (3DRA) in assessing vascular and airway narrowing in children with a bidirectional cavopulmonary anastomosis (BCPA). The course of children with single ventricle physiology is often complicated by left pulmonary artery (LPA) and/or bronchial stenosis and may be related to aortic compression. 3DRA may be useful in evaluating this complex anatomy and possible mechanisms for the observed obstruction. Clinical data and imaging (2D angiography and 3DRA) of children with a BCPA were reviewed retrospectively. Measurements were taken at similar locations along the pulmonary arteries in both modalities and in the airways on 3DRA. Twenty-five children with a previous BCPA were assessed at mean age of 3.1 ± 2.0 years and weight of 13.6 ± 3.6 kg. Excellent correlation was found between 3DRA and 2D angiographic LPA measurements (r = 0.89, p < 0.0001). Twelve children had qualitative LPA stenosis on 3DRA, with a stenotic dimension of 6.6 ± 2.2 mm on 2D angiography and 6.8 ± 1.9 mm on 3DRA (r = 0.94, p < 0.0001). Ten cases with LPA stenosis also had bronchial stenosis (83 %). Qualitative airway assessment correlated with quantitative bronchial dimensions from 3DRA-derived tomographic images: Bronchial stenosis measured 4.4 ± 1.6 versus 5.9 ± 1.1 mm in those with a normal appearing bronchus (p = 0.009). Hybrid patients (initial palliation with bilateral pulmonary artery banding and arterial ductal stenting, n = 5) and all patients with a Damus-Kaye-Stansel (DKS) anastomosis (n = 9) were more likely to have LPA and left bronchial stenosis (OR 7.7, p = 0.04). 3DRA is a useful and accurate tool in assessment of LPA and airway narrowing after BCPA. Hybrid and DKS patients are more prone to LPA and bronchial stenosis, and 3DRA can provide insight into the mechanism.

Benefits of Completion 3D Angiography Associated with Contrast Enhanced Ultrasound to Assess Technical Success after EVAR

This study evaluated a new strategy to assess technical success after standard and complex endovascular aortic repair (EVAR), combining completion contrast enhanced cone beam computed tomography (ceCBCT) and post-operative contrast enhanced ultrasound (CEUS). Patients treated with bifurcated or fenestrated and branched endografts in the hybrid room during the study period were included. From December 2012 to July 2013, a completion angiogram (CA) was performed at the end of the procedure, and computed tomography angiography (CTA) before discharge (group 1). From October 2013 to April 2014, a completion ceCBCT was performed, followed by CEUS during the 30 day post-operative period (group 2). The rate of peri-operative events (type I or III endoleaks, kinks, occlusion of target vessels), need for additional procedures or early secondary procedures, total radiation exposure (mSv), and total volume of contrast medium injected were compared. Seventy-nine patients were included in group 1 and 54 in group 2. Peri-operative event rates were respectively 8.9% (n = 7) and 33.3% (n = 18) (p = .001). Additional procedures were performed in seven patients (8.9%) in group 1 versus 17 (31.5%) in group 2 (p = .001). Two early secondary procedures were performed in group 2 (3.7%), and three (3.8%) in group 1 (p = .978). Median radiation exposure due to CBCT was 7 Gy cm(2) (5.25-8) (36%, 27%, and 9% of the total procedure exposure, respectively for bifurcated, fenestrated, and branched endografts). CEUS did not diagnose endoleaks or any adverse events not diagnosed by ceCBCT. Overall radiation and volume of contrast injected during the patient hospital stay in groups 1 and 2 were 34 (25.8-47.3) and 11 (5-20.5) mSv, and 184 (150-240) and 91 (70-132.8) mL respectively (reduction of 68% and 50%, p < .001). Completion ceCBCT is achievable in routine practice to assess technical success after EVAR. Strategies to evaluate technical success combining ceCBCT and CEUS can reduce total in hospital radiation exposure and contrast medium volume injection.

Technical and anatomical factors affecting the size of the branch pulmonary arteries following first-stage Norwood palliation for hypoplastic left heart syndrome

Branch pulmonary artery (BPA) size is one of the factors that influence the efficacy of the Fontan circulation. Central pulmonary artery stenosis and small left pulmonary artery (LPA) are well-known problems following Norwood palliation for hypoplastic left heart syndrome (HLHS). We investigated anatomical and technical factors that may stand behind these problems. A total of 47 consecutive patients were included in the study. All had complete magnetic resonance imaging (MRI) study pre-second-stage palliation. Measurements were taken using a first-pass 3D angiography technique after intravenous injection of an extravascular contrast agent. Factors investigated included the following: size and site of the pulmonary artery bifurcation stump in relation to the Damus-Kaye-Stansel (DKS) anastomosis, interaortic distance/ratio (neoaorta to descending aorta distance/antero-posterior dimension of the chest) (IAD/IAR), distance from the under surface of the arch and the size of native aorta and pulmonary artery. IAD/IAR were compared between two different arch reconstruction techniques. Stenosis occurred either centrally, at the origin of the BPA, or more distally, in the mid-LPA (posterior to DKS). There was a significant lower incidence of central BPA stenosis when the pulmonary artery stump was placed in the mid-position compared with right/left position (26 vs 67%; P = 0.011). A more bulky pulmonary artery stump was also found in those patients with central BPA stenosis (186 vs 137 mm(2)/m(2); P = 0.047). The mid-LPA consistently showed antero-posterior compression (mean cranio-caudal diameter 3.82 mm vs mean antero-posterior diameter 3.07 mm, P < 0.001). Indexed mid-LPA area was only correlated with IAD/IAR (r = 0.49 and 0.51, P < 0.001). No correlation was shown with the distance to the under surface of the arch (r = 0.14, P = 0.37), again confirming antero-posterior compression of the LPA rather than cranio-caudal. In multivariable analysis, the only predictor of indexed mid-LPA area was the IAR (P < 0.001). There was no significant difference in the IAD or IAR between the two arch reconstruction techniques [mean IAD 15.5 vs 13.5 mm (P = 0.14)]; [mean IAR 0.17 vs 0.19 (P = 0.21)]. Of all studied factors, IAR and the size and position of the pulmonary artery bifurcation plays the main role in LPA growth and central BPA stenosis.

Comparison of great artery dimensions in 3-D dual-phase SSFP, compared with 3D CE-MRA and phase-contrast imaging (magnitude image)

Background The dimensions of great vessels are measured in different methods in different institutes. The purpose of this study was to evaluate the benefits of 3D dual phase steady-state free-precession(3D-DP SSFP)for measuring great arteries dimension, compared with 3D contrastenhanced magnetic resonance angiography (3D CEMRA) and 2D phase contrast imaging (Magnitude image) (2DPC-MI), in order to find which was the most suitable and reproducible technique for follow-up. Methods 29 patients with repaired Tetralogy of Fallot or complete transposition of the great arteries after arterial switch operation (mean age 6.5yrs; range 6m to 25yrs) were included in the study. Cross-sectional diameter and area measurements were taken of the ascending aorta (Ao), main pulmonary (MPA) and branch pulmonary arteries (BPA) by using 3D DP SSFP, 3D CE-MRA and magnitude image of 2DPC-MI. Image quality was scored by a five-point scale (0 = invisible to 4 = excellent). Statistical comparison between 3D DP SSFP and other two techniques (2DPC-MI and 3D CE-MRA) was performed by using paired-t tests and Intraclass correlation coefficient. Results All great artery cross-sectional measurements were significantly (P < 0.001) greater in systole than in diastole. Measurements (diameter and area) of great arteries were greatest for 2DPC-MI, followed by 3D SSFP in systole and 3D CE-MRA, and smallest for 3D DP SSFP in