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Cardiovascular and Interventional... Aug 2020Endovascular simulation is an established and validated training method, but there is still no proof of direct patient's benefit, defined as lower complication rate. In...
PURPOSE
Endovascular simulation is an established and validated training method, but there is still no proof of direct patient's benefit, defined as lower complication rate. In this study, the impact of such a training was investigated for rehearsal of patient-specific cases as well as for a structured simulation curriculum to teach angiographer novices.
MATERIALS AND METHODS
A total of 40 patients undergoing a diagnostic neuroangiography were randomized in a training and control group. In all training group patients, the angiographer received a patient-anatomy-specific rehearsal on a high-fidelity simulator prior to the real angiography. Radiation exposure, total duration, fluoroscopy time and amount of contrast agent of the real angiography were recorded. Silent cerebral ischemia was counted by magnetic resonance diffusion-weighted imaging (DWI). Additionally, the first 30 diagnostic neuroangiographies of six novices were compared (n = 180). Three novices had undergone a structured simulation curriculum; three had acquired angiographic skills without simulation.
RESULTS
No differences were found in the number of DWI lesions or in other quality measures of the angiographies performed with and without patient-specific rehearsal. A structured simulation curriculum for angiographer novices reduced fluoroscopy time significantly and radiation exposure. The curriculum had no influence on the total duration of the examination, the amount of contrast medium or the number of catheters used.
CONCLUSION
There was no measurable benefit of patient-anatomy-specific rehearsal for an unselected patient cohort. A structured simulation-based curriculum to teach angiographic skills resulted in a reduction of fluoroscopy time and radiation dose in the first real angiographies of novice angiographers.
LEVEL OF EVIDENCE
Level 4, part 1: randomized trial, part 2: historically controlled study.
Topics: Aged; Brain Ischemia; Clinical Competence; Cohort Studies; Curriculum; Diffusion Magnetic Resonance Imaging; Female; Fluoroscopy; Humans; Magnetic Resonance Angiography; Male; Middle Aged; Radiology; Simulation Training
PubMed: 32394089
DOI: 10.1007/s00270-020-02479-5 -
Scientific Reports Mar 2020An increasing number of centers not necessarily equipped with biplane (BP) angiosuites are performing mechanical thrombectomy (MT) in acute ischemic stroke patients. We...
An increasing number of centers not necessarily equipped with biplane (BP) angiosuites are performing mechanical thrombectomy (MT) in acute ischemic stroke patients. We assessed whether MT performed on single-plane (SP) is equivalent in terms of safety, effectiveness, radiation and contrast agent exposure. Consecutive patients treated by MT in four high volume centers between January 2014 and May 2017 were included. Demographic and MT characteristics were assessed and compared between SP and BP. Of 906 patients treated by MT, 576 (64%) were handled on a BP system. After multivariate analysis, contrast load and fluoroscopy duration were significantly lower in the BP group [100vs200mL, relative effect 0.85 (CI: 0.79-0.92), p = 0.0002; 22 vs 27 min, relative effect 0.84 (CI: 0.76-0.93), p = 0.0008, respectively]. There was no difference in recanalization (modified Thrombolysis-In-Cerebral-Infarction 2b-3), good clinical outcome (modified Rankin Scale 0-2), complications rates, procedure duration or radiation exposure. A three-vessel diagnostic angiogram performed prior to MT led to a significant increase in procedure duration (15% increase, p = 0.05), radiation exposure (33% increase, p < 0.0001) and contrast load (125% increase, p < 0.0001). Mechanical neuro-thrombectomy seems equally safe and effective on a single or biplane angiography system despite increased contrast load and fluoroscopy duration on the former.
Topics: Adult; Aged; Aged, 80 and over; Angiography; Female; Humans; Male; Mechanical Thrombolysis; Middle Aged; Risk Factors; Stroke; Thrombectomy; Treatment Outcome; Young Adult
PubMed: 32161286
DOI: 10.1038/s41598-020-60851-4 -
Magnetic Resonance Imaging May 2024The integrity of vessel walls and changes in blood flow are involved in many diseases, and information about these anatomical and physiological conditions is important...
The integrity of vessel walls and changes in blood flow are involved in many diseases, and information about these anatomical and physiological conditions is important for a diagnosis. There are several different angiography methods that can be used to generate images for diagnostic purposes, but often using different imaging techniques and MR sequences. The purpose of this study was to develop a method that allows time-resolved, vessel-selective simultaneous bright and black blood imaging by vesselselective blood saturation. Measurements in six volunteers were performed to evaluate the time-resolved bright blood angiography and the significance of the generated black blood contrast. It was shown that this method can be used to generate a black blood contrast with a sufficient signal difference to the surrounding gray matter in addition to the time-resolved and vessel-selective bright blood contrast. Using post-processing methods, whole brain angiograms can be calculated from the acquired data.
Topics: Humans; Angiography; Radiography; Magnetic Resonance Angiography; Imaging, Three-Dimensional
PubMed: 38309377
DOI: 10.1016/j.mri.2024.01.019 -
Nature Communications Apr 2020In today's clinics, a cell-resolution view of the cornea can be achieved only with a confocal microscope (IVCM) in contact with the eye. Here, we present a common-path...
In today's clinics, a cell-resolution view of the cornea can be achieved only with a confocal microscope (IVCM) in contact with the eye. Here, we present a common-path full-field/spectral-domain OCT microscope (FF/SD OCT), which enables cell-detail imaging of the entire ocular surface in humans (central and peripheral cornea, limbus, sclera, tear film) without contact and in real-time. Real-time performance is achieved through rapid axial eye tracking and simultaneous defocusing correction. Images contain cells and nerves, which can be quantified over a millimetric field-of-view, beyond the capability of IVCM and conventional OCT. In the limbus, palisades of Vogt, vessels, and blood flow can be resolved with high contrast without contrast agent injection. The fast imaging speed of 275 frames/s (0.6 billion pixels/s) allows direct monitoring of blood flow dynamics, enabling creation of high-resolution velocity maps. Tear flow velocity and evaporation time can be measured without fluorescein administration.
Topics: Adult; Angiography; Biomedical Engineering; Blood Flow Velocity; Cornea; Equipment Design; Female; Humans; Limbus Corneae; Male; Microscopy; Optical Imaging; Software; Tomography, Optical Coherence; Young Adult
PubMed: 32313067
DOI: 10.1038/s41467-020-15792-x -
Radiology and Oncology Dec 2023Optical coherence tomography angiography (OCTA) is an emerging imaging modality that enables noninvasive visualization and analysis of tumor vasculature. OCTA has been... (Review)
Review
BACKGROUND
Optical coherence tomography angiography (OCTA) is an emerging imaging modality that enables noninvasive visualization and analysis of tumor vasculature. OCTA has been particularly useful in clinical ocular oncology, while in this article, we evaluated OCTA in assessing microvascular changes in clinical nonocular oncology through a systematic review of the literature.
METHOD
The inclusion criterion for the literature search in PubMed, Web of Science and Scopus electronic databases was the use of OCTA in nonocular clinical oncology, meaning that all ocular clinical studies and all ocular and nonocular animal, phantom, ex vivo, experimental, research and development, and purely methodological studies were excluded.
RESULTS
Eleven articles met the inclusion criteria. The anatomic locations of the neoplasms in the selected articles were the gastrointestinal tract (2 articles), head and neck (1 article) and skin (8 articles).
CONCLUSIONS
While OCTA has shown great advancements in ophthalmology, its translation to the nonocular clinical oncology setting presents several limitations, with a lack of standardized protocols and interpretation guidelines posing the most significant challenge.
Topics: Tomography, Optical Coherence; Angiography
PubMed: 38038417
DOI: 10.2478/raon-2023-0057 -
Computer Methods and Programs in... Mar 2023Automatic segmentation of the cerebral vasculature and aneurysms facilitates incidental detection of aneurysms. The assessment of aneurysm rupture risk assists with...
BACKGROUND AND OBJECTIVES
Automatic segmentation of the cerebral vasculature and aneurysms facilitates incidental detection of aneurysms. The assessment of aneurysm rupture risk assists with pre-operative treatment planning and enables in-silico investigation of cerebral hemodynamics within and in the vicinity of aneurysms. However, ensuring precise and robust segmentation of cerebral vessels and aneurysms in neuroimaging modalities such as three-dimensional rotational angiography (3DRA) is challenging. The vasculature constitutes a small proportion of the image volume, resulting in a large class imbalance (relative to surrounding brain tissue). Additionally, aneurysms and vessels have similar image/appearance characteristics, making it challenging to distinguish the aneurysm sac from the vessel lumen.
METHODS
We propose a novel multi-class convolutional neural network to tackle these challenges and facilitate the automatic segmentation of cerebral vessels and aneurysms in 3DRA images. The proposed model is trained and evaluated on an internal multi-center dataset and an external publicly available challenge dataset.
RESULTS
On the internal clinical dataset, our method consistently outperformed several state-of-the-art approaches for vessel and aneurysm segmentation, achieving an average Dice score of 0.81 (0.15 higher than nnUNet) and an average surface-to-surface error of 0.20 mm (less than the in-plane resolution (0.35 mm/pixel)) for aneurysm segmentation; and an average Dice score of 0.91 and average surface-to-surface error of 0.25 mm for vessel segmentation. In 223 cases of a clinical dataset, our method accurately segmented 190 aneurysm cases.
CONCLUSIONS
The proposed approach can help address class imbalance problems and inter-class interference problems in multi-class segmentation. Besides, this method performs consistently on clinical datasets from four different sources and the generated results are qualified for hemodynamic simulation. Code available at https://github.com/cistib/vessel-aneurysm-segmentation.
Topics: Humans; Deep Learning; Angiography; Neural Networks, Computer; Aneurysm; Brain; Image Processing, Computer-Assisted
PubMed: 36709557
DOI: 10.1016/j.cmpb.2023.107355 -
BMJ Open Mar 2023In the care of coronary artery disease (CAD), evidence questions the adequate application of guidelines for cardiovascular procedures, particularly coronary... (Review)
Review
OBJECTIVES
In the care of coronary artery disease (CAD), evidence questions the adequate application of guidelines for cardiovascular procedures, particularly coronary angiographies (CA) and myocardial revascularisation. This review aims to examine how care providers' guideline adherence for CA and myocardial revascularisation in the care of chronic CAD was assessed in the literature.
DESIGN
Scoping review.
DATA SOURCES
PubMed and EMBASE were searched through in June 2021 (rerun in September 2022).
ELIGIBILITY CRITERIA
We included studies assessing care providers' adherence to evidence-based guidelines for CA or myocardial revascularisation in the care of chronic CAD. Studies had to list the evaluation of guideline adherence as study objective, describe the evaluation methods used and report the underlying guidelines and recommendations.
DATA EXTRACTION AND SYNTHESIS
Two independent reviewers used standardised forms to extract study characteristics, methodological aspects such as data sources and variables, definitions of guideline adherence and quantification methods and the extent of guideline adherence. To elucidate the measurement of guideline adherence, the main steps were described.
RESULTS
Twelve studies (311 869 participants) were included, which evaluated guideline adherence by (1) defining guideline adherence, (2) specifying the study population, (3) assigning (classes of) recommendations and (4) quantifying adherence. Thereby, primarily secondary data were used. Studies differed in their definitions of guideline adherence, where six studies each considered only recommendation class I/grade A/strong recommendations as adherent or additionally recommendation classes IIa/IIb. Furthermore, some of the studies reported a priori definitions and allocation rules for the assignment of recommendation classes. Guideline adherence results ranged from 10% for percutaneous coronary intervention with prior heart team discussion to 98% for coronary artery bypass grafting.
CONCLUSION
Due to remarkable inconsistencies in the assessment, a cautious interpretation of the guideline adherence results is required. Future efforts should endeavour to establish a consistent understanding of the concept of guideline adherence.
Topics: Humans; Coronary Artery Disease; Guideline Adherence; Coronary Artery Bypass; Myocardial Revascularization; Coronary Angiography
PubMed: 36921955
DOI: 10.1136/bmjopen-2022-069832 -
Korean Journal of Radiology Feb 2022To determine the usefulness of Silent MR angiography (MRA) for evaluating intracranial aneurysms treated with stent-assisted coil embolization.
OBJECTIVE
To determine the usefulness of Silent MR angiography (MRA) for evaluating intracranial aneurysms treated with stent-assisted coil embolization.
MATERIALS AND METHODS
Ninety-nine patients (101 aneurysms) treated with stent-assisted coil embolization (Neuroform atlas, 71 cases; Enterprise, 17; LVIS Jr, 9; and Solitaire AB, 4 cases) underwent time-of-flight (TOF) MRA and Silent MRA in the same session using a 3T MRI system within 24 hours of embolization. Two radiologists independently interpreted both MRA images retrospectively and rated the image quality using a 5-point Likert scale. The image quality and diagnostic accuracy of the two modalities in the detection of aneurysm occlusion were further compared based on the stent design and the site of aneurysm.
RESULTS
The average image quality scores of the Silent MRA and TOF MRA were 4.38 ± 0.83 and 2.78 ± 1.04, respectively ( < 0.001), with an almost perfect interobserver agreement. Silent MRA had a significantly higher image quality score than TOF MRA at the distal internal carotid artery (n = 57, 4.25 ± 0.91 vs. 3.05 ± 1.16, < 0.001), middle cerebral artery (n = 21, 4.57 ± 0.75 vs. 2.19 ± 0.68, < 0.001), anterior cerebral artery (n = 13, 4.54 ± 0.66 vs. 2.46 ± 0.66, < 0.001), and posterior circulation artery (n = 10, 4.50 ± 0.71 vs. 2.90 ± 0.74, = 0.013). Silent MRA had superior image quality score to TOF MRA in the stented arteries when using Neuroform atlas (4.66 ± 0.53 vs. 3.21 ± 0.84, < 0.001), Enterprise (3.29 ± 1.59 vs. 1.59 ± 0.51, = 0.003), LVIS Jr (4.33 ± 1.89 vs. 1.89 ± 0.78, = 0.033), and Solitaire AB stents (4.00 ± 2.25 vs. 2.25 ± 0.96, = 0.356). The interpretation of the status of aneurysm occlusion exhibited significantly higher sensitivity with Silent MRA than with TOF MRA when using the Neuroform Atlas stent (96.4% vs. 14.3%, respectively, < 0.001) and LVIS Jr stent (100% vs. 20%, respectively, = 0.046).
CONCLUSION
Silent MRA can be useful to evaluate aneurysms treated with stent-assisted coil embolization, regardless of the aneurysm location and type of stent used.
Topics: Angiography, Digital Subtraction; Cerebral Angiography; Embolization, Therapeutic; Follow-Up Studies; Humans; Intracranial Aneurysm; Magnetic Resonance Angiography; Retrospective Studies; Stents; Treatment Outcome
PubMed: 35029075
DOI: 10.3348/kjr.2021.0332 -
Zhurnal Voprosy Neirokhirurgii Imeni N.... 2015
Review
Topics: Cerebral Angiography; Cerebrovascular Disorders; Fluorescein Angiography; Humans; Video Recording
PubMed: 25909744
DOI: 10.17116/neiro201579142-47 -
Canadian Association of Radiologists... May 2017Stroke is the second leading cause of mortality and the third leading cause of disability-adjusted life-years worldwide. For each minute of an ischemic stroke, an... (Review)
Review
Stroke is the second leading cause of mortality and the third leading cause of disability-adjusted life-years worldwide. For each minute of an ischemic stroke, an estimated 1.9 million brain cells die. The year 2015 saw the unprecedented publication of 5 multicentre, randomized, controlled trials. These studies showed that patients with acute ischemic stroke caused by large-vessel thrombus occlusion of the proximal anterior circulation had significantly reduced disability at 90 days when treated with endovascular thrombectomy and usual stroke care compared to usual stroke care alone. As a result, endovascular thrombectomy is now the new North American and European standard of care for suitable patients with acute ischemic stroke caused by large-vessel proximal anterior circulation occlusion. We review key take-home messages in this paradigm shift for radiologists, including the importance of time and workflow efficiency, what currently constitutes appropriate preimaging patient selection and imaging criteria, the use of newer generation thrombectomy devices, safety outcomes, as well as further areas still in need of elucidation.
Topics: Age Factors; Angiography; Brain Ischemia; Endovascular Procedures; Humans; Magnetic Resonance Angiography; Patient Selection; Sex Factors; Stroke; Thrombectomy; Time Factors; Tomography, X-Ray Computed
PubMed: 28131334
DOI: 10.1016/j.carj.2016.10.002