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Journal of Nuclear Cardiology :... Jun 2021
Topics: Angiography; Echocardiography; Gated Blood-Pool Imaging; Humans; Reproducibility of Results; Stroke Volume; Tricuspid Valve Insufficiency; Ventricular Function, Left
PubMed: 31350716
DOI: 10.1007/s12350-019-01826-5 -
Physics in Medicine and Biology Jul 2021Vessel centerline extraction from x-ray angiography images is essential for vessel structure analysis in the diagnosis of coronary artery disease. However, complete and...
Vessel centerline extraction from x-ray angiography images is essential for vessel structure analysis in the diagnosis of coronary artery disease. However, complete and continuous centerline extraction remains a challenging task due to image noise, poor contrast, and complexity of vessel structure. Thus, an iterative multi-path search framework for automatic vessel centerline extraction is proposed. First, the seed points of the vessel structure are detected and sorted by confidence. With the ordered seed points, multi-bifurcation centerline is searched through multi-path propagation of wavefront and accumulated voting. Finally, the centerline is further extended piecewise by wavefront propagation on the basis of keypoint detection. The latter two steps are performed alternately to obtain the final centerline result. The proposed method is qualitatively and quantitatively evaluated on 1260 synthetic images and 50 clinical angiography images. The results demonstrate that our method has a highF1score of 87.8% ± 2.7% for the angiography images and achieves accurate and continuous results of vessel centerline extraction.
Topics: Algorithms; Angiography; Coronary Angiography
PubMed: 34157702
DOI: 10.1088/1361-6560/ac0d8e -
Developments in Ophthalmology 2016Optical coherence tomography (OCT) angiography (OCT-A) is a transformative approach in imaging ocular vessels based on flow rather than simple reflectance intensity. It... (Review)
Review
Optical coherence tomography (OCT) angiography (OCT-A) is a transformative approach in imaging ocular vessels based on flow rather than simple reflectance intensity. It is therefore a functional extension of OCT that can be used to visualize microvasculature by detecting motion contrast from flowing blood. As OCT-A is a depth-resolved examination, it needs careful axial segmentation in order to preserve important data on perfused structures and to avoid the risk of generating superimposed images, which are typical of dye angiographies. An automated segmentation algorithm for both retinal and choroidal layers is provided by the majority of different OCT-A devices. In the case of accentuated macular retinal/choroidal disruptions causing potential segmentation errors, specific manual correction allows one to modify the shape and the localization of each layer. In the case of manual segmentation, the thickness of every C-scan may be modified in order to provide a constant thickness of tissue slices at different retinal or choroidal levels. OCT projection artifacts also occur from superficial retinal vessels, which can be seen in deeper retinal layers, or retinal and choroidal vessels, which can even be seen in the scleral tissue. These projection artifacts are almost always present and are visible in any layer that is located below the perfused vasculature.
Topics: Angiography; Animals; Artifacts; Choroid; Diagnostic Techniques, Ophthalmological; Fluorescein Angiography; Humans; Image Processing, Computer-Assisted; Imaging, Three-Dimensional; Regional Blood Flow; Retinal Vessels; Tomography, Optical Coherence
PubMed: 27023365
DOI: 10.1159/000442774 -
Angiology Jan 2020
Topics: China; Coronary Angiography; Fractional Flow Reserve, Myocardial; Percutaneous Coronary Intervention
PubMed: 31084188
DOI: 10.1177/0003319719848559 -
European Journal of Radiology Jun 2021Pulsatile tinnitus (PT) can be a mild or debilitating symptom. Following clinical examination and otoscopy, when the underlying aetiology is not apparent, radiological... (Review)
Review
Pulsatile tinnitus (PT) can be a mild or debilitating symptom. Following clinical examination and otoscopy, when the underlying aetiology is not apparent, radiological imaging can be used to evaluate further. CT arteriography-venography (CT A-V) of the head and neck has recently been introduced as a single 'one catch' modality for identifying the many causes of PT including those which are treatable and potentially serious whilst also providing reassurance through negative studies or studies with benign findings. CT A-V is performed as a single phase study allowing both arterial and venous assessment, hence limiting radiation exposure. Additional multiplanar reformats and bone reconstructions are desirable. Understanding the limitations of CT A-V is also required, with an awareness of the scenarios where other imaging modalities should be considered. The causes of PT can be divided into systemic and non-systemic categories. Non-systemic aetiologies in the head and neck should be carefully reviewed on CT A-V and include a variety of vascular causes (arteriovenous malformations/fistulas, venous or arterial aetiologies) and non-vascular causes (tumours and bony dysplasias). Venous causes (dominant, aberrant, stenosed or thrombosed venous vessels) are more common than arterial aetiologies (aberrant or stenosed internal carotid artery, aneurysms or a persistent stapedial artery). Glomus tumours that are not visible on otoscopy and osseous pathologies such as bony dehiscence and otospongiosis should also be excluded. Careful assessment of all the potential vascular and non-vascular causes should be reviewed in a systematic approach, with correlation made with the clinical history. A structured reporting template for the reporting radiologist is provided in this review to ensure all the potential causes of PT are considered on a CT A-V study. This will help in providing a comprehensive radiological evaluation, hence justifying the radiation dose and for patient assessment and prognostication.
Topics: Aneurysm; Angiography; Arteriovenous Fistula; Humans; Phlebography; Tinnitus
PubMed: 33894642
DOI: 10.1016/j.ejrad.2021.109722 -
Developments in Ophthalmology 2016To describe the optical coherence tomography angiography (OCTA) features of diabetic retinopathy. (Review)
Review
PURPOSE
To describe the optical coherence tomography angiography (OCTA) features of diabetic retinopathy.
METHODS
Literature review and case series.
RESULTS
Four cases are presented.
CONCLUSION
OCTA is an effective method for evaluating retinal changes in diabetic retinopathy and represents a novel complement or alternative to fluorescein angiography. Although OCTA should currently be considered an investigational technique, in the near future, it may play key roles in the diagnosis and management of diabetic retinopathy.
Topics: Angiography; Diabetic Retinopathy; Fluorescein Angiography; Humans; Retinal Vessels; Tomography, Optical Coherence
PubMed: 27023453
DOI: 10.1159/000442801 -
Graefe's Archive For Clinical and... Feb 2023
Topics: Humans; Tomography, Optical Coherence; Retinal Diseases; Choroid; Angiography; Fluorescein Angiography; Retinal Vessels
PubMed: 36322215
DOI: 10.1007/s00417-022-05879-0 -
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 -
JACC. Cardiovascular Imaging Dec 2020Coronary artery disease remains the leading cause of cardiovascular morbidity and mortality. Invasive X-ray angiography and coronary computed tomography angiography are... (Review)
Review
Coronary artery disease remains the leading cause of cardiovascular morbidity and mortality. Invasive X-ray angiography and coronary computed tomography angiography are established gold standards for coronary luminography. However, they expose patients to invasive complications, ionizing radiation, and iodinated contrast agents. Among a number of imaging modalities, coronary cardiovascular magnetic resonance (CMR) angiography may be used in some cases as an alternative for the detection and monitoring of coronary arterial stenosis, with advantages including its versatility, excellent soft tissue characterization, and avoidance of ionizing radiation and iodinated contrast agents. In this review, we explore the recent advances in motion correction, image acceleration, and reconstruction technologies that are bringing coronary CMR angiography closer to widespread clinical implementation.
Topics: Computed Tomography Angiography; Coronary Angiography; Coronary Artery Disease; Coronary Stenosis; Humans; Magnetic Resonance Angiography; Predictive Value of Tests
PubMed: 32199836
DOI: 10.1016/j.jcmg.2020.01.006 -
Radiology Sep 2022
Topics: Humans; Magnetic Resonance Angiography; Phlebography
PubMed: 35536135
DOI: 10.1148/radiol.213208