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Introduction: Mapping and ablation through the coronary venous system (CVS) have shown potential for ventricular arrhythmias originating from the left ventricular summit (LVS). Multielectrode catheters and balloons are frequently used for mapping and venous ethanol ablation (VEA). However, there is limited data on the venous size and drainage condition in the LVS region. This study aimed to investigate the morphology, angiographic size, and drainage condition of LV summit veins via high‐speed rotational angiography (RA). Methods: We measured and analyzed the size of the great cardiac vein (GCV), the anterior interventricular vein (AIV), veins near to the LVS, and other main tributaries of CVS in 102 patients undergoing electrophysiology study. Results: Rotational retrograde angiography of LVS was successfully performed in 81 patients. The diameter of GCV at the level of the Vieussens valve and the distal end of GCV (junction of GCV‐AIV) was larger in males than females (6.8 ± 1.1 vs. 5.6 ± 1.2 mm, p <.001; 5.2 ± 0.9 vs. 4.6 ± 0.8, p =.002, respectively) while no significant gender differences were observed in other tributaries. The LV summit veins presented downward drainage direction in half of the patients, indicating potential anatomic adjacency with His bundle. Left anterior oblique (LAO) 45° projection might provide the practical and optimal view of the LV summit veins. Conclusions: The coronary veins of the LVS region present various anatomical morphologies and ostium sizes. We provide a systematic description and angiographic size spectrum of CVS. RA could facilitate assessing the feature of CVS comprehensively. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study is to evaluate the branching patterns and topographical features of the third part of the maxillary artery (t-MA) and descending palatine artery (DPA) by 3-Dimensional Rotational Angiography (3DRA) images and to define the radiological classification of their variations, based upon the previous cadaveric studies and a review of the literature. Method: This study was conducted from May 2020 through June 2021. All consecutive adult patients who were examined with 3D-RA were enrolled in the study. The morphological evaluations and measurements of t-MA, DPA and their branches were made on maximum intensity projection images with 10–20 mm slice thickness. Results: Eighty-five hemifaces, including 58 females and 45 right sides, were evaluated. The diameter of the t-MA was measured as 1.73 ± 0.30 mm. The most common pattern of the t-MA according to its course was loop type (63/85, 74.1%) and according to branching pattern was Type Ib (29/85, 34.1%). The mean diameter of DPA was 1.19 ± 0.20 mm. The DPA presented as a single trunk in 11/85 cases. Type II, which was defined as one lesser palatine artery originating from distal-DPA, was the most common morphological variation (51.8%). Conclusions: 3DRA imaging provides valuable information for vascular anatomical studies. The most common morphological variation related to t-MA, DPA is the distal branching pattern. [ABSTRACT FROM AUTHOR]

Cone-beam computed tomography (CBCT) images for skull base tumors provide detailed vascular information and localization in regard to surrounding bony structures. We report use of the CBCT fusion technique for skull base meningiomas. Six patients with petroclival or petrotentorial meningiomas supplied by multiple arterial systems were preoperatively evaluated using CBCT fusion imaging. Fusion images were reconstructed from three-dimensional rotational angiography with contrast agent injections from the internal carotid artery (ICA) and external carotid artery in 4 cases, vertebral artery and external carotid artery in 1 case, and ICA and vertebral artery in 1 case. The feeding pedicles and tumor stains from 2 arterial systems were differentiated by separate colors. The courses and territories of the ICA dural feeders or ICA/vertebral artery pial feeders were easily distinguished from the external carotid artery dural feeders. Anastomoses between thin feeders from different arterial systems could be detected. Mixed stain (stain with both colors) was observed in some tumor compartments, suggesting dual supply from 2 arterial systems and the presence of peritumoral anastomoses. All patients underwent preoperative embolization without complications. CBCT fusion images clearly visualized the feeders from each arterial system, the vascular compartments within the tumor, and possible peritumoral anastomoses. This technique provides a substantial contribution to both preoperative embolization and surgical resection of skull base meningiomas. [ABSTRACT FROM AUTHOR]

This proof of principle study assesses the utility of contrast-enhance ultrasound (CEUS) and contrast-enhanced tomographic 3-D ultrasound (CEtUS), as an intra-procedural imaging tool after endovascular-aneurysm repair (EVAR), compared with rotational angiography. A total of 20 consecutive patients undergoing infra-renal EVAR underwent immediate post-deployment rotational angiography, followed by CEUS and CEtUS scans. Outcomes were presence of endoleak, renal artery patency and endograft deformity. CEUS and CEtUS detected 12 endoleaks, 8 of which were not detected by rotational angiography. CEUS and CEtUS classify 7 or 8 type IIb endoleaks not detected by rotational angiography. CEUS/CEtUS could not identify 12 and 13 renal arteries, respectively, detected by rotational angiography. Rotational angiography and CEtUS both identified 1 endograft limb deformity, corrected immediately. CEUS and CEtUS are more sensitive to type II endoleak than rotational angiography, although there is a lower detection of renal arteries. CEUS or CEtUS has the utility for immediate post-EVAR endoleak detection where reduction of contrast agent is indicated. [ABSTRACT FROM AUTHOR]

Cardiac catheterization is a commonly used form of imaging and treatment in pediatric patients with congenital heart disease. Traditionally, two-dimensional conventional angiography was the method used, but since 2000 three-dimensional rotational angiography (3DRA) is increasingly used in the field of cardiology in both adult and pediatric patients. To investigate the use and applications of 3DRA in pediatric congenital cardiology, literature was systematically reviewed and 29 eligible articles were found. Those showed that 3DRA is already a greatly valued diagnostic and therapeutic technique in pediatric cardiology. However, the literature misses well-designed clinical, homogeneous, multicenter, prospective studies recording data in a standardized manner. These studies are necessary to ensure proper data analysis and to investigate the true advantages of 3DRA and how it exactly benefits the patients. [ABSTRACT FROM AUTHOR]

Previously, median effective dose (ED) of 1.6 mSv per three-dimensional rotational angiography (3DRA) has been reported. This study evaluated ED and image quality in 3DRA after implementation of a simple dose reduction protocol in pediatric catheterizations. Simple conversion factors between 3DRA ED and readily available parameters at the cathlab were determined. The dose reduction protocol consisted of frame reduction (60-30 frames/s (f/s)), active collimation of the X-ray beam, usage of a readily available low dosage program, and a pre-3DRA run check. EDs were calculated with Monte Carlo PCXMC 2.0. Three observers blindly assessed 3DRA image quality of the dose reduction and normal-dose cohort. Between October 2014 and October 2015, 84 patients (median age 4.3 years) underwent 100 3DRAs with a median ED of 0.54 mSv (0.12-2.2) using the dose reduction protocol. Median ED in the normal-dose cohort (17 3DRAs) was 1.6 mSv (1.2-4.9). Image quality in the dose reduction cohort remained excellent. Correlations between ED and dose area product (DAP) and ED and skin dose were found with a ρ of 0.82 and 0.83, respectively. ED exposure of the entire catheterization was reduced to 2.64 mSv. Introduction of a simple protocol led to 66% dose reduction in 3DRA and 79% in the entire catheterization. 3DRA image quality in this group remained excellent. In 3DRA ED correlates well with DAP and skin dose, parameters readily available at the cathlab. [ABSTRACT FROM AUTHOR]

It is important to visually confirm radiofrequency ablation lesions during atrial fibrillation (AF) ablation for procedural efficiency, which requires the integration of a three-dimensional (3D) left atrial image reconstructed from computed tomography (CT) or a magnetic resonance imaging. However, an EP Navigator allows seamless integration of 3D anatomy obtained through 3D rotational angiography (3D-ATG) into an electroanatomical mapping system. We hypothesized that 3D-ATG can be used during AF ablation while significantly reducing the effective dose (ED) and without compromising image morphology compared to a 3D-CT image. Organ dose was measured at 37 points with a radiophotoluminescence glass dosimeter inserted in an anthropomorphic Rando Phantom. The ED was calculated by multiplying the organ dose by the tissue weighting factor. The dose-area product (DAP)-to-ED conversion factor was calculated by measuring the DAP during radiation exposure. The ED for the CT examination was estimated from the dose-length product with a conversion factor of 0.014. ED was calculated from DAP measurements in 114 patients undergoing AF ablation using 3D-ATG. The DAP-to-ED conversion factor for 3D-ATG was 2.4 × 10−4 mSv/mGy cm2 in our hospital. The mean DAP for all patients was 7777 ± 1488 mGy cm2 for the 3D-ATG of the left atrium. The corresponding ED for 3D-ATG was 1.9 ± 0.4 mSv. The ED for CT examinations was 13.6 ± 4.2 mSv (P < 0.001). 3D-ATG can be used during AF ablation while significantly reducing the ED and without compromising image morphology. [ABSTRACT FROM AUTHOR]

Background This study aimed to evaluate the detailed location and the number (single or multiple) of cavernous sinus dural arteriovenous fistula (CSDAVF) shunted pouches as well as the relationship between the characteristics of shunted pouch(es) and the treatment outcome of transvenous embolization for CSDAVF. Methods A total of 23 consecutive patients with CSDAVFs who underwent angiogram and transvenous embolization were retrospectively analyzed. Shunted pouches were assessed using three-dimensional angiogram and multiplanar reformatted image obtained from the rotational angiogram data. Results Of the 23 patients with CSDAVFs, 40 shunted pouches were identified. Twelve CSDAVFs had a single shunted pouch, and 11 had multiple shunted pouches. The mean CSDAVF with multiple shunted pouches was 2.5. The shunted pouches were more often found in the posterior compartment of the CS, which was connected with the intercavernous sinus (23/40; 57.5%). In 12 CSDAVFs with a single shunted pouch, 10 were treated with selective embolization and complete occlusion was achieved during the follow-up. Two CSDAVFs with single shunted pouch were just observed without intervention, and DAVFs disappeared spontaneously during the follow-up period. In 11 CSDAVFs with multiple shunted pouches, eight were treated with selective embolization and three with sinus embolization. In six of eight (75%), complete occlusion was achieved following selective embolization, but two of eight (25%) recurred and required retreatment. Conclusions Rotational angiography data suggested that the shunted pouches of CSDAVFs were mostly located in the posterior compartment of the CS connected with the intercavernous sinus. Selective embolization for CSDAVFs with a single shunted pouch is the first-line treatment alternative to sinus packing, and selective embolization with multiple shunted pouches will be a considerable treatment option. [ABSTRACT FROM AUTHOR]

Rotational angiography (RA) has proven to be an excellent method for evaluating congenital disease (CHD) in the cardiac cath lab, permitting acquisition of 3D datasets with superior spatial resolution. This technique has not been routinely implemented for 3D printing in CHD. We describe our case series of models printed from RA and validate our technique. All patients with models printed from RA were selected. RA acquisitions from a Toshiba Infinix-I system were postprocessed and printed with a Stratasys Eden 260. Two independent observers measured 5-10 points of interest on both the RA and the 3D model. Bland Altman plot was used to compare the measurements on rotational angiography to the printed model. Models were printed from RA in 5 patients (age 2 months-1 year). Diagnoses included (a) coronary artery aneurysm, (b) Glenn shunt, (c) coarctation of the aorta, (d) tetralogy of Fallot with MAPCAs, and (e) pulmonary artery stenosis. There was no significant measurement difference between RA and the printed model (r = 0.990, p < 0.01, Bland Altman p = 0.987). There was also no significant inter-observer variability. The MAPCAs model was referenced by the surgeon intraoperatively and was accurate. Rotational angiography can generate highly accurate 3D models in congenital heart disease, including in small vascular structures. These models can be extremely useful in patient evaluation and management. [ABSTRACT FROM AUTHOR]

Introduction The digital subtraction angiography is considered the gold standard in detecting cerebral aneurysms. Other less invasive techniques that require a lesser dose of contrast medium are currently employed such as rotational angiography (RA) and computed tomography angiography with three-dimensional reconstruction (3D-CTA). The aim of this study is to recommend 3D-CTA as a screening test for cerebral aneurysms in patients with suspected cerebrovascular pathology, having compared it to other tests requiring the use of less contrast medium, in this case, RA and 3D-CTA. Materials and Methods The study was performed between 2010 and 2014 among all patients referred to the Centro Médico Nacional "20 de Noviembre" ISSSTE, in Mexico City, presenting a total of 332 patients with suspected cerebral aneurysm; 182 patients who had undergone angiography or digital subtraction angiography in a different hospital were not included, and 50 patients who tested negative for cerebral aneurysm were also excluded. Experts in neurological imaging examined the results, comparing those diagnosed with cerebral aneurysms, using RA and 3D-CTA against the gold standard. Results Both RA and 3D-CTA registered the same aneurysm dimensions. Differences were observed in aneurysm's dome only. Conclusion The RA should be reserved for those cases where a DSA is deemed necessary, but cannot be performed due to the high amount of contrast medium required and risk of adverse reactions in allergic population; in this case, the 3D-CTA is a better test. [ABSTRACT FROM AUTHOR]

Aim Rotational angiography is a well-known method for the three-dimensional (3-D) reconstruction of left atrium and pulmonary veins during left-sided atrial arrhythmia ablation procedures. In our study, we aimed to review our experience in transseptal puncture ( TSP) using 3-D rotational angiography. Methods We included a total of 271 patients who underwent atrial fibrillation ablation using cryoballoon. Rotational angiography was performed to get the three-dimensional left atrial and pulmonary vein reconstructions using cardiac C-arm computed tomography. The image reconstruction was made using the Dyna CT Cardiac software (Siemens, Erlangen, Germany). Results The mean age of the study population was 61 ± 10 years. The indications for left atrial arrhythmia ablation were paroxysmal AF in 140 patients (52%) and persistent AF patients in 131 (48%) patients. The success rate of TSP using only rotational guidance was (264/271 patients, 97.4%). In the remaining seven patients, transesophageal guidance was used after the initial attempt due to thick interatrial septum in five patients and difficult TSP due to abnormal anatomy and mild pericardial effusion in the remaining two patients. Mean fluoroscopy dosage of the rotational angiography was 4896.4 ± 825.3 μGym2. The mean time beginning from femoral vein puncture to TSP was 12.3 ± 5.5 min. Conclusion TSP guided by rotational angiography is a safe and effective method. Our results indicate that integration of rotational angiographic images into the real-time fluoroscopy can guide the TSP during the procedure. [ABSTRACT FROM AUTHOR]

Objectives: Endovascular embolization is a valid option for the management of visceral artery aneurysms. Imaging is crucial for providing anatomical assessments, but preoperative non-invasive investigations may not be exhaustive. The aim of this work is to present preliminary experience with the use of three-dimensional rotational angiography (3DRA) in this particular theatre.Methods: Seven patients were treated for eight visceral aneurysms (six splenic and two renal) by endovascular embolization. 3DRA was performed before the treatment using a standard protocol. Different parameters (location of the lesion, the afferent and efferent vessels, aneurysm neck, vascular diameters, working incidence) were analyzed.Results: 3DRA was successfully accomplished in all procedures. Mean aneurysm diameter was 23 mm and mean C-arm working incidence was 29° (R-L) and 9° (C-C). The sandwich technique was used in four lesions and the packing in the remaining four. Technical success was 100 %. The mean radiation dose per procedure was 291 600 mGy.cm(2). The mean procedural time was 2.25 hours. There were no immediate or short-term complications.Conclusions: 3DRA could be an interesting intraoperative tool to provide anatomical and technical assessments of the visceral arteries necessary for endovascular treatment, especially when information from preoperative imaging is not exhaustive.Key Points: Endovascular embolization is a valid alternative solution for visceral artery aneurysm treatment. Imaging is crucial for anatomical assessments and treatment guidance. 3DRA can contribute to endovascular treatment in lieu of preoperative imaging. [ABSTRACT FROM AUTHOR]

Abstract: Tracking the location of medical devices in interventional X-ray data solves different problems. For example the motion information of the devices is used to determine cardiac or respiratory motion during X-ray guided procedures or device features are used as landmarks to register images. In this publication an approach using a 3D deformable catheter model is presented and used to track a coronary sinus (CS) catheter in 3D plus time through a complete rotational angiography sequence. The benefits of using voxel based models with attenuation information for 2D/3D registration are investigated in comparison to binary catheter models. The 2D/3D registration of the model allows to extract a 3D catheter shape from every individual 2D projection. The tracking accuracy is evaluated on simulated and clinical rotational angiography data of the contrast enhanced left atrium. The quantitative evaluation of the experiments delivers an average registration accuracy for all catheter electrodes of 0.23mm in 2D and 0.95mm in 3D when using an attenuation model of the catheter. The overall tracking accuracy is lower when using binary catheter models. [Copyright &y& Elsevier]

Abstract: Background: Coronary angiography (CA) has been the gold standard technique for studying coronary artery disease. It is based on the analysis of bidimensional orthogonal projections that may not be optimal to estimate determinate coronary segments. Rotational angiography “Xperswing” (DARCA) is a new technique that allows the visualization of the coronary arteries from multiple views, with a single contrast injection. The aim of this study is to evaluate the coronary lesions quantification with DARCA. Methods: Quantitative coronary analysis of significant coronary stenosis (>50%) was performed. Every lesion was measured in two different projections: the “optimal projection”, obtained by DARCA and defined by the operator as the one with a better lesion qualification, and the “standard projection”, corresponding to the usual projection closer to the optimal one in obliquity and angulation. Measures were performed twice and by two independent operators. Intra- and inter-observer correlation was estimated by Kappa index and variables were compared with t Student test (SPSS 14.0). Results: 205 lesions in 147 patients were analyzed. Kappa coefficient intra-observer was 0.80 and 0.86 respectively with an inter-observer correlation index of 0.72. Lesion length and maximal diameter of the vessel were significantly greater in the group of RA. In the segments analysis, calculated length was longer for the first diagonal branch, first marginal obtuse artery, middle circumflex, middle and distal RCA and posterior descending artery, with greater reference diameters for proximal LAD and distal RCA. There were no significant differences for coronary stenosis grade. Conclusions: RA XperSwing provides a better visualization of coronary arteries improving lesions characterization, with longer measured lesions length and greater vessel diameters, especially in coronary segments with more angulation. [Copyright &y& Elsevier]

Abstract: Primary hyperaldosteronism due to aldosterone secreting adrenal adenomas is an important and potentially curable cause for hypertension. The differentiation between unilateral or bilateral adrenal adenomas is crucial, as unilateral adenomas can easily be cured by surgery whereas bilateral adenomas have to be treated conservatively. Exact diagnosis can be made when unilateral or bilateral hormone production is proven with adrenal vein sampling. We present an effective step-by-step technique how to perform an adrenal vein sampling with a special emphasis on how to reliably catheterize the right adrenal vein using Dyna CT. [Copyright &y& Elsevier]

Rotational angiography is a novel method for three-dimensional reconstruction of the left atrium and pulmonary veins during catheter ablation for atrial fibrillation, but is still hampered by suboptimal reconstructions in a considerable number of patients. We describe the results of rapid pacing of the right ventricle for optimization of image acquisition during rotational angiography. [ABSTRACT FROM AUTHOR]

DynaCT Cardiac Integration into Electroanatomical Mapping. Introduction: Exact visualization of complex left atrial (LA) anatomy is crucial for safety and success rates when performing catheter ablation of atrial fibrillation (AF). The aim of our study was to validate the accuracy of integrating rotational angiography-based 3-dimensional (3D) reconstructions of LA and pulmonary vein (PV) anatomy into an electroanatomical mapping (EAM) system. Methods and Results: In 38 patients (62 ± 8 years, 25 females) undergoing catheter ablation of paroxysmal (n = 19) or persistent (n = 19) AF, intraprocedural rotational angiography of LA and PVs was performed. The subsequent 3D reconstruction and segmentation of LA and PVs was transferred to the EAM system and registered to the EAM. The distances of all EAM points to corresponding points on the LA syngo® DynaCT Cardiac surface were calculated. Segmentation of LA with clear visualization of adjacent structures was possible in all patients. Also, the integrated segmentation of the LA was used to guide the encirclement of ipsilateral veins, which resulted in PV isolation in all patients. Integration into the 3D mapping system was achieved with a distance error of 2.2 ± 0.4 mm when compared with the EAM surface. Subgroups with paroxysmal and persistent AF showed distance errors of 2.3 ± 0.3 mm and 2.1 ± 0.4 mm, respectively (P = n.s.). Conclusion: Intraprocedural registration of LA and PV anatomy by contrast enhanced rotational angiography was feasible and accurate. There were no differences between patients with paroxysmal or persistent AF. Therefore, integration of rotational angiography-based reconstructions into 3D EAM systems might be helpful to guide catheter ablation for AF. [ABSTRACT FROM AUTHOR]

Abstract: X-ray doses (delivered) to the patients during coronary angiography (CA) and percutaneous coronary intervention (PCI) show ability of one certain deterious effects and can be sometimes at very high level. According to the European directives, all the equipments allowing to make diagnostic and interventional procedure integrate a unit of measure of the Dose Area Product. This measure is associated in a linear way with the effective dose and allows to measure the stochastic risk, the indicator also of good practices. Stemming from general vascular rotational acquisition technology, the cardiac rotational angiography is potentially beneficial for the patients and the operators concerning the exposure in ionizing radiations. The purpose of this study is to measure retrospectively the various dominating indicators in the irradiation of the patients on a series of case realized from January, 2009 till May, 2009 further to the implementation of this technique of acquisition. The dose area product, the duration of fluoroscopy as well as the number of acquired images were measured after coronary angiogram at 250 consecutive patients between January, 2009 and May, 2009. The procedures were realized by four operators, using the femoral access. The dose area product, the durations of fluoroscopy as well as the number of images has been respectively of 39,3Gycm2 [4,7–210,65Gycm2], 8,4minutes [0,8–38minutes] and 575 frames [175–1427 frames] in standard coronary angiogram; 33,64Gycm2 [4,95–85,6Gycm2], 2,8minutes [1,1–26minutes], 503 frames [314–836 frames] in single rotational coronary angiogram; 24,26Gycm2 [5,74–51,1Gycm2], 3,9minutes [1,3–14minutes], 272 frames [127–429 frames] in double rotational coronary angiogram. In conclusion, the exposure of the patient to the X-rays, the practitioners and paramedical in interventional cardiology depends on the operator, on the fluoroscopy time and on the number of acquired images. The double rotational angiography is one of the solution to achieve these objectives. [Copyright &y& Elsevier]

Abstract: Cardiologists use two-dimensional projection images in conventional X-ray coronary angiography for the assessment of three-dimensional structures. During minimally invasive interventions there is a need to clearly visualize and analyze contrast filled coronary arteries, surrounding tissue, and implanted devices. Three-dimensional reconstruction of these structures is challenging due to the cardiac and respiratory motion. In this paper we describe a method to automatically generate motion compensated reconstructions of various structures using rotational X-ray angiography. The method uses markers on a device or guide wire to identify and estimate the motion of an object or region of interest in order to register and motion compensate the projection images to generate a motion compensated reconstruction. The method is evaluated on 20 rotational acquisitions and the average marker couple detection rate is 84% for cardiac stents, 90% for closure devices and 20% for contrast filled coronaries. The projection images are motion compensated based on the semi-automatically detected markers and subsequently used for reconstruction. We conclude that it is feasible to reconstruct cardiac stents, closure devices, contrast filled coronaries, and calcified plaques using rotational X-ray angiography. [Copyright &y& Elsevier]

We describe a 22-year-old woman admitted to hospital in emergency with nuchal headache and vomiting. CT scan disclosed subarachnoid hemorrhage. Digital subtraction angiography with three-dimensional rotational acquisitions showed a ruptured aneurysm of a right persistent primitive hypoglossal artery as the cause of symptoms and hemorrhage. The patient was successfully treated with endovascular coiling of the aneurysm. This is the second literature report describing endovascular treatment in this unusual condition. [ABSTRACT FROM AUTHOR]

Abstract: For assessment of cerebrovascular diseases, it is beneficial to obtain three-dimensional (3D) information on vessel morphology and haemodynamics. Rotational angiography is routinely used to determine the 3D geometry. In this paper, we propose a method to exploit the same acquisition to determine the blood flow waveform and the mean volumetric flow rate in the large cerebral arteries. The method uses a model of contrast agent dispersion to determine the flow parameters from the spatial and temporal progression of the contrast agent concentration, represented by a flow map. Furthermore, it overcomes artefacts due to the rotation (overlapping vessels and foreshortened vessels at some projection angles) of the C-arm using a reliability map. The method was validated on images from different phantom experiments. We analysed different properties of the flow quantification method, including the influence of noise and the influence of the length of the analysed blood vessel. In most cases, the relative error was between 5% and 10% for the volumetric mean flow rate and between 10% and 15% for the blood flow waveform. The manual interaction took at most one minute and the computational time for the flow quantification was between 4 and 20min on a PC. From this, we conclude that the method has the potential to give quantitative estimates of blood flow parameters during cerebrovascular interventions. [Copyright &y& Elsevier]

For the assessment of cerebrovascular diseases, it is beneficial to obtain three-dimensional (3D) morphologic and hemodynamic information about the vessel system. Rotational angiography is routinely used to image the 3D vascular geometry and we have shown previously that rotational subtraction angiography has the potential to also give quantitative information about blood flow. Flow information can be determined when the angiographic sequence shows inflow and possibly outflow of contrast agent. However, a standard volume reconstruction assumes that the vessel tree is uniformly filled with contrast agent during the whole acquisition. If this is not the case, the reconstruction exhibits artifacts. Here, we show how flow information can be used to support the reconstruction of the 3D vessel centerline and radii in this case. Our method uses the fast marching algorithm to determine the order in which voxels are analyzed. For every voxel, the rotational time intensity curve (R-TIC) is determined from the image intensities at the projection points of the current voxel. Next, the bolus arrival time of the contrast agent at the voxel is estimated from the R-TIC. Then, a measure of the intensity and duration of the enhancement is determined, from which a speed value is calculated that steers the propagation of the fast marching algorithm. The results of the fast marching algorithm are used to determine the 3D centerline by backtracking. The 3D radius is reconstructed from 2D radius estimates on the projection images. The proposed method was tested on computer simulated rotational angiography sequences with systematically varied x-ray acquisition, blood flow, and contrast agent injection parameters and on datasets from an experimental setup using an anthropomorphic cerebrovascular phantom. For the computer simulation, the mean absolute error of the 3D centerline and 3D radius estimation was 0.42 and 0.25 mm, respectively. For the experimental datasets, the mean absolute error of the 3D centerline was 0.45 mm. Under pulsatile and nonpulsatile conditions, flow information can be used to enable a 3D vessel reconstruction from rotational angiography with inflow and possibly outflow of contrast agent. We found that the most important parameter for the quality of the reconstruction of centerline and radii is the range through which the x-ray system rotates in the time span of the injection. Good results were obtained if this range was at least 135°. As a standard c-arm can rotate 205°, typically one third of the acquisition can show inflow or outflow of contrast agent, which is required for the quantification of blood flow from rotational angiography. [ABSTRACT FROM AUTHOR]

This paper proposes a novel computational methodology for modelling the haemodynamic effects of endovascular coil embolization for cerebral aneurysms. We employ high-resolution 3-D angiographic data to reconstruct the intracranial geometry and we model the coiled part of the aneurysm as a porous medium, with porosity decreasing as coils are inserted. The actual dimensions of the coils employed are used to determine the characteristics of the porous medium. Simulation results for saccular aneurysms from the anterior communicating and middle cerebral arteries show that insertion of coils rapidly changes intraaneurysmal blood flow and causes reduction in mural pressure and blood velocity up to stagnation, providing favorable conditions for thrombus formation and obliteration of the aneurysm. [ABSTRACT FROM AUTHOR]

Intracranial angioplasty and stenting (ICAS) is a therapeutic option in symptomatic intracranial atherosclerotic disease. Adequate follow-up examination is necessary to exclude in-stent restenosis. Conventional intraarterial digital subtraction angiography (ia-DSA) is the current gold standard, but it is an invasive technique and carries the risk of neurological complications. Angiographic CT (ACT) is a new technique that provides a volume dataset of the highest spatial resolution and high contrast resolution derived from a rotational acquisition of a c-arm-mounted flat-panel detector. The feasibility of ACT with intravenous administration of contrast medium (iv-ACT) for follow-up after ICAS is demonstrated. In two patients iv-ACT was performed as a follow-up examination 12 months after ICAS. High-resolution volume data from the rotational acquisitions were processed to provide delineation of the stent lumen as well as imaging of the brain parenchyma and vessels. In both patients the patency of the stent lumen was assessed successfully. In addition, all other brain vessels were displayed in a manner similar to their appearance on CT angiograms. The brain parenchyma was also adequately imaged in a manner similar to its appearance on CT images. We demonstrated the feasibility and diagnostic value of iv-ACT for follow-up imaging after ICAS. This new application has the potential to become the imaging method of choice after ICAS since it not only enables visualization of the patency of the stent lumen but also is minimally invasive and provides additional information about all brain arteries and the brain parenchyma. [ABSTRACT FROM AUTHOR]

Abstract: Background: Three-dimensional rotational angiography has recently been implemented in many interventional neuroradiology practices and may assist the endovascular operator in case selection and planning. The end result may be improved safety. Methods: We retrospectively searched our database for all aneurysms that were treated at our institution since February 1990. We identified 2 groups—those treated before and after the installation of our rotational fluoroscope on April 23, 2003. Patients with extracranial or intracavernous aneurysms were excluded. If multiple treatments were performed, only the first embolizations were considered. We then compared the 2 groups with regard to rates of immediate procedural complications. We further stratified aneurysms by number, size, and neck dimension, and performed subgroup analyses. We also conducted a post hoc comparison between chronological epochs within each group to determine whether improved safety was an epiphenomenon of advances in technology or operator skill. Results: There were a total of 876 patients treated before and 337 after the implementation of 3D-RA (total N = 1213). The overall complication rate in the pre-3D group was 5.9% and 3.0% in the post-3D group (odds ratio, 0.48; 95% CI, 0.24-0.97). Complication rates were also decreased for patients with single aneurysms. Post hoc analysis demonstrated no benefit within chronological subgroups of the pre-3D or post-3D cohorts. This suggests that the improved safety profile after 3D-RA implementation is not an epiphenomenon of factors such as technological advances or experiential improvements in technique. Conclusions: 3D-RA implemented during endovascular therapy for intracranial aneurysms improves the safety of the procedure. This may be a result of either improved aneurysm analysis and thus case selection, improved working position selection, or both. [Copyright &y& Elsevier]

The purpose of this paper is to derive a technique for accelerating the computation of cone-beam forward and backward projections that are the basic steps of tomographic reconstruction. The cone-beam geometry of C-arm systems is commonly described with projection matrices. Such matrices provide a continuous framework for analyzing the flow of operations needed to compute backprojection for analytical reconstruction, as well as the combination of forward and backward projections for iterative reconstruction. The proposed rectification technique resamples the original data to planes that are aligned with two of the reconstructed volume main axes, so that the original cone-beam geometry can be replaced by a simpler geometry, where succession of plane magnifications are involved only. Rectification generalizes previous independent results to the cone-beam backprojection of preprocessed data as well as to cone-beam iterative reconstruction. The memory access pattern of simple magnifications provides superior predictability and is, therefore, easier to optimize, independently of the choice of the interpolation technique. Rectification is also shown to provide control over interpolation errors through oversampling, allowing tradeoffs between computation speed and precision to be set. Experimental results are provided for linear and nearest neighbor interpolations, based on simulations, as well as phantom and patient data acquired on a digital C-arm system. [ABSTRACT FROM AUTHOR]

Hemodynamic factors are thought to be implicated in the progression and rupture of intracranial aneurysms. Current efforts aim to study the possible associations of hemodynamic chars acteristics such as complexity and stability of intra-aneurysmal flow patterns, size and location of the region of flow impingement with the clinical history of aneurysmal rupture. However, there are no reliable methods for measuring blood flow patterns in vivo. In this paper, an efficient methodology for patient-specific modeling and characterization of the hemodynamics in cerebral aneurysms from medical images is described. A sensitivity analysis of the hemodynamic characteristics with respect to variations of several variables over the expected physiologic range of conditions is also presented. This sensitivity analysis shows that although changes in the velocity fields can be observed, the characterization of the intra-aneurysmal flow patterns is not altered when the mean input flow, the flow division, the viscosity model, or mesh resolution are changed. It was also found that the variable that has the greater impact on the computed flow fields is the geometry of the vascular structures. We conclude that with the proposed modeling pipeline clinical studies involving large numbers cerebral aneurysms are feasible. [ABSTRACT FROM AUTHOR]

Abstract: The incidence of adverse events complicating coronary angiography is still considerably high. Founded concerns about risks of coronary angiography, and mainly its inherent invasiveness, have favored the increasing request for noninvasive techniques to evaluate the coronary anatomy, such as multislice computed tomography (MSCT). Nonetheless, it has to be kept in mind that several risks and complications are the same both for MSCT and conventional coronary angiography. Rotational angiography has been shown to be a powerful imaging tool for the evaluation of coronary anatomy resulting in the use of less contrast media and less radiation, without losing the possibility to obtain a precise, efficient and fast characterization of obstructive coronary artery disease. It is likely that in the next future the overall performance, taking into account both the diagnostic accuracy and the risk of exposure to radiation and contrast media, of MSCT techniques will have to be compared to that of rotational angiography, especially when the latter is coupled with minimally invasive approaches. [Copyright &y& Elsevier]

Background: Cardiac catheterization continues to be the gold standard in the management of CHD because of its diagnostic accuracy and therapeutic advantages. Among the recent advances in cardiac catheterization is the use of 3DRA which has been introduced in CHDs nearly 10 years ago after its long use in neuroradiology with good outcomes. Objective: The aim of this work is to describe our initial experience with rotational angiography at Ain Shams University and compare between conventional and rotational angiography in terms of contrast, radiation and procedure time. Patients and Methods: The study included 100 patients presenting to Ain Shams University Hospital pediatric cath lab in the period between February 2017 and July 2018. Fifty patients underwent rotational angiography (RA) and 50 underwent conventional angiography. The 2 groups were matched regarding age, sex, weight, diagnosis and the procedure performed. Results: The median age in the study was 4 years with a median weight of 15.5 kg. The study included 44 patients with PDA, 42 (95%) underwent PDA closure. 30 patients had PS of which 28 underwent BPV (93%). 8 patients had CoA, 6 had CoA balloon +/- stenting (75%). 12 patients were postGlenn, 2 had TOF, 2 had AS and 2 had history of TOF repair with either RPA or LPA stenosis. Diagnostic quality imaging was obtained in 74% of cases. The RA cases were divided into earlier and later groups which were compared with each other and with the conventional angiography group. The procedure time decreased significantly in the later RA cases (38 minutes compared to 49 minutes in earlier cases) but was still significantly more than the conventional angiography group (33 minutes). Total contrast decreased in later cases (3.56 ml/kg) but was still more than conventional angiography cases (2.55 ml/kg). Less DAP was needed in later RA cases than earlier cases and conventional cases (10 Graycm2, 24 Graycm2 and 16 Graycm2 respectively). The more procedure time in RA group can be explained by the time lost in preparing the room for 3DRA and processing of the reconstructed image. The more contrast is related to the routine use of biplane in conventional group and the simplicity of procedures involved in our study requiring little contrast and fewer injections in conventional angiography. Conclusion: RA can be safely performed in diagnostic and interventional cases for better visualization of extra cardiac structures with significant reduction of radiation exposure on the expense of some more time and contrast. RA requires time to master it in a way that makes it a valuable additional tool in the cath lab. [ABSTRACT FROM AUTHOR]