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Journal of Glaucoma Jun 2022Face mask wearing has no significant effects on artifacts or vessel density measurements in optic nerve head (ONH) and macular optical coherence tomography-angiography...
PRCIS
Face mask wearing has no significant effects on artifacts or vessel density measurements in optic nerve head (ONH) and macular optical coherence tomography-angiography (OCT-A) scans.
PURPOSE
The aim was to assess the difference in area of artifacts observed in optical OCT-A scans with and without face mask wear and to verify if mask wear interferes with OCT-A vessel density measurements.
SUBJECTS AND CONTROLS
A total of 64 eyes of 10 healthy subjects, 4 ocular hypertensive, 8 glaucoma suspects, and 17 glaucoma patients were included.
MATERIALS AND METHODS
High-density ONH and macula OCT-A scans were obtained in patients with and without surgical masks. Seven different artifacts (motion, decentration, defocus, shadow, segmentation failure, blink, and Z-offset) were quantitatively evaluated by 2 trained graders. The changes in the area (% of scan area) of artifacts, without and with mask wearing, and differences of vessel density were evaluated.
RESULTS
Trends of increasing motion artifact area for the ONH scans [4.23 (-0.52, 8.98) %, P=0.08] and defocus artifact area for the macular scans [1.06 (-0.14, 2.26) %, P=0.08] were found with face mask wear. However, there were no significant differences in the mean % area of any artifacts (P>0.05 for all). Further, the estimated mean difference in vessel density in images acquired without and with masks was not significant for any type of artifact.
CONCLUSION
Face mask wearing had no significant effect on area of artifacts or vessel density measurements. OCT-A vessel density measurements can be acquired reliably with face mask wear during the pandemic.
Topics: Angiography; Artifacts; COVID-19; Fluorescein Angiography; Glaucoma; Humans; Intraocular Pressure; Masks; Pandemics; Retinal Vessels; Tomography, Optical Coherence
PubMed: 35320142
DOI: 10.1097/IJG.0000000000002019 -
Diagnostic and Interventional Radiology... Sep 2019Although peripheral nerve injuries secondary to angiography and endovascular interventions are uncommon and usually not permanent, they can result in significant... (Review)
Review
Although peripheral nerve injuries secondary to angiography and endovascular interventions are uncommon and usually not permanent, they can result in significant functional impairment. Most arteries used in access for angiography and endovascular therapies lie in close proximity to a nerve. The nerve may be injured by needle puncture, or by compression from hematoma, pseudoaneurysm, hemostasis devices, or by manual compression with incidence in literature ranging from as low as 0.04% for femoral access in a large retrospective study to 9% for brachial and axillary access. Given the increasing frequency of endovascular arterial procedures and the increasing use of nontraditional access points, it is important that the interventionalist have a working knowledge of peripheral nerve anatomy and function as it relates to relevant arterial access sites to avoid injury.
Topics: Angiography; Endovascular Procedures; Humans; Peripheral Nerve Injuries; Punctures; Risk Factors
PubMed: 31310240
DOI: 10.5152/dir.2019.18296 -
Tomography (Ann Arbor, Mich.) Dec 2022This study aimed to optimize velocity-selective magnetic resonance angiography (VS-MRA) protocols for whole-neck angiography and demonstrate its feasibility in healthy...
This study aimed to optimize velocity-selective magnetic resonance angiography (VS-MRA) protocols for whole-neck angiography and demonstrate its feasibility in healthy subjects with comparisons to clinical 3D time-of-flight (TOF) angiography. To help optimize VS-MRA protocols, 2D phase-contrast (PC) flow imaging and 3D B and B field mappings were performed on five healthy volunteers. Based on these measurements, a slab-selective (SS) inversion preparation was applied prior to a VS saturation preparation to further suppress venous blood, while the VS preparation pulse was designed with compensation for field offsets. VS-MRA and 3D TOF were performed on six healthy subjects, and relative contrast ratios (CRs) between artery and muscle signals were calculated for twenty arterial regions for comparisons. The pre-compensated VS pulse improved the visualization of the subclavian arteries and suppression of background tissues, which involved large B and B field errors. The combination of SS and VS preparations effectively suppressed venous blood. While the relative CR values were 0.78 ± 0.08 and 0.72 ± 0.10 for VS-MRA and 3D TOF, respectively, over the twenty segments, VS-MRA outperformed 3D TOF in visualizing arterial segments of a small size or with a horizontal orientation, such as subclavian, facial, and occipital arteries. The proposed neck VS-MRA with the field-error-compensated VS preparation combined with the SS preparation is feasible and superior to 3D TOF in visualizing small and/or horizontally oriented arterial segments.
Topics: Humans; Magnetic Resonance Angiography; Magnetic Resonance Imaging; Arteries; Magnetic Resonance Spectroscopy
PubMed: 36648993
DOI: 10.3390/tomography9010006 -
Magma (New York, N.Y.) Oct 2020Coronary magnetic resonance angiography (coronary MRA) is advantageous in its ability to assess coronary artery morphology and function without ionizing radiation or... (Review)
Review
Coronary magnetic resonance angiography (coronary MRA) is advantageous in its ability to assess coronary artery morphology and function without ionizing radiation or contrast media. However, technical limitations including reduced spatial resolution, long acquisition times, and low signal-to-noise ratios prevent it from clinical routine utilization. Nonetheless, each of these limitations can be specifically addressed by a combination of novel technologies including super-resolution imaging, compressed sensing, and deep-learning reconstruction. In this paper, we first review the current clinical use and motivations for non-contrast coronary MRA, discuss currently available coronary MRA techniques, and highlight current technical developments that hold unique potential to optimize coronary MRA image acquisition and post-processing. In the final section, we examine the various research-based coronary MRA methods and metrics that can be leveraged to assess coronary stenosis severity, physiological function, and atherosclerotic plaque characterization. We specifically discuss how such technologies may contribute to the clinical translation of coronary MRA into a robust modality for routine clinical use.
Topics: Contrast Media; Coronary Angiography; Coronary Vessels; Heart; Magnetic Resonance Angiography
PubMed: 32242282
DOI: 10.1007/s10334-020-00834-8 -
Colorectal Disease : the Official... Jul 2021This study aims to evaluate the extrinsic effects of conditional factors affecting quantitative parameters and to establish the optimization of indocyanine green (ICG)... (Observational Study)
Observational Study
AIM
This study aims to evaluate the extrinsic effects of conditional factors affecting quantitative parameters and to establish the optimization of indocyanine green (ICG) angiography using in vitro experiments and a prospective observational study.
METHOD
In vitro experiments were performed to evaluate the correlation between conditional factors such as camera distance, surrounding lighting, fluorescence emission sources and ICG doses. The fluorescence intensity was measured from the ICG-containing test tube in each condition. In the clinical study, ICG angiography was applied to patients with colorectal cancer (n = 164). The quantitative perfusion parameters were the maximal fluorescence intensity (F ), slope, T and perfusion time ratio (TR). Camera position, distance to colon, fluorescence emission source, surrounding lighting, site of angiography and ICG specific mode were considered as conditional factors and compared with the quantitative parameters to identify the optimal condition of ICG angiography.
RESULTS
The fluorescence intensity had an inverse correlation with distance, and the transitional zone was shown at a distance of 4-5 cm by slope differential. F , T and slope were affected significantly by camera distance, site of angiography, fluorescence emission source and ICG mode as conditional factors. On multivariate analysis, F was independently associated with spectral ICG mode with red inversion, laser mode and camera distance. Conversely, TR was not related to any conditional factors.
CONCLUSION
Since quantitative parameters of ICG angiography are influenced by various conditions, a standardized protocol is required. The application of ICG specific modes with a constant distance of 4-5 cm can provide optimized fluorescence images.
Topics: Anastomotic Leak; Angiography; Colorectal Neoplasms; Colorectal Surgery; Fluorescein Angiography; Humans; Indocyanine Green; Laparoscopy; Perfusion
PubMed: 33894016
DOI: 10.1111/codi.15684 -
Clinical Neuroradiology Jun 2021Simulators are increasingly used in the training of endovascular procedures; however, for the use of the Mentice vascular interventional system trainer (VIST) simulator...
PURPOSE
Simulators are increasingly used in the training of endovascular procedures; however, for the use of the Mentice vascular interventional system trainer (VIST) simulator in neuroradiology, the validity of the method has not yet been proven. The study was carried out to test the construct validity of such a simulator by demonstrating differences between beginner and expert neurointerventionalists and to evaluate whether a training effect can be demonstrated in repeated cases for different levels of experience.
METHODS
In this study 4 experts and 6 beginners performed 10 diagnostic angiographies on the VIST simulator (Mentice AB, Gothenburg, Sweden). Of the cases four were non-recurring, whereas three were repeated once and ten subjects performed all tasks. Additionally, another expert performed only five non-recurring cases. The simulator recorded total time, fluoroscopy time, amount of contrast medium and number of material changes. Furthermore, gaze direction and heart rate were recorded, and subjects completed a questionnaire on workload.
RESULTS
Beginners and experts showed significant differences in total duration time, fluoroscopy time and amount of contrast agent (all p < 0.05). Gaze direction, dwell time and heart rate were similar between both groups. Only beginners improved during training with respect to total duration time, fluoroscopy time and amount of contrast agent. If a case was previously known to them, the total duration and fluoroscopy time were significantly shortened (p < 0.001).
CONCLUSION
This study demonstrated both the construct validity of a diagnostic neuroangiography simulator as well as a significant training effect for beginners. Therefore, in particular beginner neurointerventionalists should use such simulation tools more extensively in their initial training.
Topics: Angiography; Clinical Competence; Computer Simulation; Fluoroscopy; Humans; Simulation Training; User-Computer Interface
PubMed: 32303789
DOI: 10.1007/s00062-020-00902-5 -
Computers in Biology and Medicine Jul 2021Optical coherence tomography angiography (OCTA) and fluorescein angiography (FA) are two different vascular imaging modalities widely used in clinical practice to...
Optical coherence tomography angiography (OCTA) and fluorescein angiography (FA) are two different vascular imaging modalities widely used in clinical practice to diagnose and grade different relevant retinal pathologies. Although each of them has its advantages and disadvantages, the joint analysis of the images produced by both techniques to analyze a specific area of the retina is of increasing interest, given that they provide common and complementary visual information. However, in order to facilitate this analysis task, a previous registration of the pair of FA and OCTA images is desirable in order to superimpose their common areas and focus the gaze on the regions of interest. Normally, this task is manually carried out by the expert clinician, but it turns out to be tedious and time-consuming. Here, we present a three-stage methodology for robust multimodal registration of FA and superficial plexus OCTA images. The first one is a preprocessing stage devoted to reducing the noise and segmenting the main vessels in both types of images. The second stage uses the vessel information to do an approximate registration based on template matching. Lastly, the third stage uses an evolutionary algorithm based on differential evolution to refine the previous registration and obtain the optimal registration. The method was evaluated in a dataset with 172 pairs of FA and OCTA images, obtaining a success rate of 98.8%. The best mean execution time of the method was less than 5 s per image.
Topics: Algorithms; Fluorescein Angiography; Retina; Retinal Vessels; Tomography, Optical Coherence
PubMed: 34126283
DOI: 10.1016/j.compbiomed.2021.104529 -
Survey of Ophthalmology 2023An array of retinochoroid imaging modalities aid in comprehensive evaluation of the immunopathological changes in the retina and choroid, forming the core component for... (Review)
Review
An array of retinochoroid imaging modalities aid in comprehensive evaluation of the immunopathological changes in the retina and choroid, forming the core component for the diagnosis and management of inflammatory disorders such as uveitis. The recent technological breakthroughs have led to the development of imaging platforms that can evaluate the layers of retina and choroid and the structural and functional alteration in these tissues. Ophthalmologists heavily rely on imaging modalities such as dye-based angiographies (fluorescein angiography and indocyanine green angiography), optical coherence tomography, fundus autofluorescence, as well as dye-less angiography such as optical coherence tomography angiograph,y for establishing a precise diagnosis and understanding the pathophysiology of the diseases. Furthermore, these tools are now being deployed with a 'multimodal' approach for swift and accurate diagnosis. In this comprehensive review, we outline the imaging platforms used for evaluation of posterior uveitis and discuss the organized, algorithmic approach for the assessment of the disorders. Additionally, we provide an insight into disease-specific characteristic pathological changes and the established strategies to rule out disorders with overlapping features on imaging.
Topics: Humans; Multimodal Imaging; Uveitis, Posterior; Uveitis; Fluorescein Angiography; Fundus Oculi; Tomography, Optical Coherence; Choroid
PubMed: 36724831
DOI: 10.1016/j.survophthal.2023.01.006 -
Heart & Lung : the Journal of Critical... 2023Computational tomography coronary angiography (CTCA) is increasingly the diagnostic test of choice for investigating patients with stable anginal symptoms. (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Computational tomography coronary angiography (CTCA) is increasingly the diagnostic test of choice for investigating patients with stable anginal symptoms.
OBJECTIVES
We sought to conduct a systematic review and meta-analysis comparing CTCA with invasive coronary angiography (ICA) with regards to major adverse cardiovascular events (MACE), procedural complications and rates of revascularisation.
METHODS
We conducted a systematic review and meta-analysis in line with the PRISMA statement. A literature search was conducted using PubMed, MEDLINE Ovid and Embase, with three studies included in meta-analysis. Statistical analysis was undertaken using Review Manager 5.3 for MacOS software and outcomes expressed as odds ratio, with 95% confidence intervals and sensitivity analysis was conducted.
RESULTS
A total of 5662 patients were included in this study level meta-analysis. There was no difference in MACE between CT and angiography [2.97% v 3.45%, fixed-effect model, OR: 0.84 (0.62-1.14), p = 0.26, I 0%] and no difference found in rates of myocardial infarction, death or stroke. CTCA was associated with a reduced rate of revascularisation [12.6% v 18.3%, fixed-effects model, OR: 0.64 (0.55-0.75), p<0.00001, I =0%]. However, CTCA was not associated with a significantly lower complication rate [0.5% v 1.72%, random effects model, OR: 0.52 (0.06-4.38), p = 0.55, I 52%].
CONCLUSION
CTCA is a safe strategy for investigating patients with stable angina with no associated increase in MACE but a reduction in revascularisation rates.
Topics: Humans; Computed Tomography Angiography; Coronary Artery Disease; Coronary Angiography; Myocardial Infarction; Heart
PubMed: 36257218
DOI: 10.1016/j.hrtlng.2022.09.018 -
Deutsches Arzteblatt International Jun 2019
Topics: Computed Tomography Angiography; Coronary Angiography; Fractional Flow Reserve, Myocardial; Tomography, X-Ray Computed
PubMed: 31431249
DOI: 10.3238/arztebl.2019.0460a