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Atherosclerosis Feb 2023
Topics: Humans; Computed Tomography Angiography; Artificial Intelligence; Carotid Arteries; Plaque, Atherosclerotic; Angiography; Carotid Stenosis; Coronary Angiography
PubMed: 36682983
DOI: 10.1016/j.atherosclerosis.2023.01.006 -
Ultrasound in Medicine & Biology Oct 2020Cancerous tumor growth is associated with the development of tortuous, chaotic microvasculature, and this aberrant microvascular morphology can act as a biomarker of... (Review)
Review
Cancerous tumor growth is associated with the development of tortuous, chaotic microvasculature, and this aberrant microvascular morphology can act as a biomarker of malignant disease. Acoustic angiography is a contrast-enhanced ultrasound technique that relies on superharmonic imaging to form high-resolution 3-D maps of the microvasculature. To date, acoustic angiography has been performed with dual-element transducers that can achieve high contrast-to-tissue ratio and resolution in pre-clinical small animal models. In this review, we first describe the development of acoustic angiography, including the principle, transducer design, and optimization of superharmonic imaging techniques. We then detail several preclinical applications of this microvascular imaging method, as well as the current and future development of acoustic angiography as a pre-clinical and clinical diagnostic tool.
Topics: Acoustics; Angiography; Animals; Contrast Media; Forecasting; Humans; Microvessels; Neoplasms; Neovascularization, Pathologic; Ultrasonography
PubMed: 32703659
DOI: 10.1016/j.ultrasmedbio.2020.06.009 -
Developments in Ophthalmology 2016Optical coherence tomography angiography (OCT-A) is a promising new method for visualizing the retinal vasculature and choroidal vascular layers in the macular area and... (Review)
Review
Optical coherence tomography angiography (OCT-A) is a promising new method for visualizing the retinal vasculature and choroidal vascular layers in the macular area and provides depth-resolved functional information on blood flow in these vessels. OCT-A is based on the concept that in a static eye the only moving structure in the fundus of the eye is blood flowing through the vessels. Contrast is generated based on the difference between moving cells in the vasculature and the static surrounding tissue. Artifacts can arise due to scan positioning errors caused by normal ocular microsaccades. In order to avoid artifacts, a sequence of OCT B-scans in the exact same retinal location must be taken to detect flow. Active eye-tracking (TruTrackā¢) using the simultaneous acquisition of fundus and optical coherence tomography (OCT) images presents a very reliable method of acquiring OCT volume scans without motion artifacts and helps significantly improve signal-to-noise ratio. This system also allows the use of a full spectrum amplitude decorrelation algorithm that produces clear differentiation between blood flow and static tissue without sacrificing the axial resolution of OCT images. Accuracy in layer segmentation, which requires high-resolution OCT B-scans, is crucial for producing reliable OCT-A images. This can be achieved through automated or manual layer segmentation. During OCT scan acquisition, the effect of axial motion (e.g. a patient moving towards the camera) is compensated for by geometric alignment of successive B-scans before analyzing temporal changes.
Topics: Angiography; Choroid; Diagnostic Techniques, Ophthalmological; Fluorescein Angiography; Humans; Retinal Vessels; Tomography, Optical Coherence
PubMed: 27022921
DOI: 10.1159/000442768 -
Developments in Ophthalmology 2016Optical coherence tomography angiography (OCTA) can be used to visualize alterations in the choriocapillaris of patients with dry age-related macular degeneration (AMD).... (Review)
Review
Optical coherence tomography angiography (OCTA) can be used to visualize alterations in the choriocapillaris of patients with dry age-related macular degeneration (AMD). These changes seem to be present during all stages of the disease. Earlier stages are associated with patchy thinning of the choriocapillaris, while geographic atrophy is associated with loss of choriocapillaris lying under the area of geographic atrophy and asymmetric alteration of choriocapillaris at the margins of the geographic atrophy. The use of high-speed, long-wave-length swept-source OCT for angiography, with its better penetration into the choroid and high acquisition speeds, enable OCTA with scaled slowest detectable flow and fastest distinguishable flow. This will enable us to better investigate choriocapillaris changes in patients with dry AMD. The ability to image the choriocapillaris structure and flow impairments may be useful in the future for detecting and monitoring the progression of dry AMD and for monitoring treatment responses in clinical trials to therapies that target disease progression in dry AMD.
Topics: Angiography; Geographic Atrophy; Humans; Tomography, Optical Coherence
PubMed: 27023214
DOI: 10.1159/000442784 -
Revue Medicale Suisse Aug 2022Hematuria is frequently encountered in clinical practice. Its diagnostic spectrum is wide: urinary tract infection, lithiasis, malignant tumor and nephropathy. In the...
Hematuria is frequently encountered in clinical practice. Its diagnostic spectrum is wide: urinary tract infection, lithiasis, malignant tumor and nephropathy. In the absence of one of these causes, the nutcracker syndrome must be evoked. It results from compression of the left renal vein between the abdominal aorta and the superior mesenteric artery. Knowing how to diagnose it can avoid morbid consequences (chronic renal disease, renal vein thrombosis). In addition to hematuria, its main symptoms are left lumbago, varicoceles, and orthostatic proteinuria. The clinical picture and complementary examinations (ultrasound-doppler, computed tomography angiography, magnetic resonance angiography, and phlebography) generally allow the diagnosis to be made. Treatment varies according to age and severity of symptoms.
Topics: Angiography; Hematuria; Humans; Male; Phlebography; Renal Veins; Syndrome
PubMed: 36004658
DOI: 10.53738/REVMED.2022.18.792.1566 -
Pediatric Radiology Feb 2022Non-contrast magnetic resonance (MR) angiography and MR venography techniques are gaining popularity for vascular imaging because they are faster, more forgiving and... (Review)
Review
Non-contrast magnetic resonance (MR) angiography and MR venography techniques are gaining popularity for vascular imaging because they are faster, more forgiving and less costly compared with contrast-enhanced MR angiography. Non-contrast MR angiography also avoids gadolinium deposition, which is especially important in imaging children. Non-contrast MR angiography has an array of specific applications for numerous clinical indications. This review summarizes the non-contrast MR angiography methods and their relative advantages and disadvantages. The paper also guides the reader on which technique to consider when determining the optimal imaging modality for each individual patient.
Topics: Child; Contrast Media; Gadolinium; Humans; Magnetic Resonance Angiography; Magnetic Resonance Imaging; Phlebography
PubMed: 33893543
DOI: 10.1007/s00247-021-05067-y -
Catheterization and Cardiovascular... Aug 2017
Topics: Angiography; Anniversaries and Special Events; Diffusion of Innovation; Forecasting; History, 20th Century; History, 21st Century; Humans; Percutaneous Coronary Intervention; Societies, Medical
PubMed: 28805029
DOI: 10.1002/ccd.27201 -
International Angiology : a Journal of... Feb 2023A properly performed pulse examination can provide an accurate assessment of the arterial circulation to the lower extremity. However, increasing availability of...
A properly performed pulse examination can provide an accurate assessment of the arterial circulation to the lower extremity. However, increasing availability of non-invasive vascular laboratory testing, CT-angiography, magnetic resonance angiography, and catheter-based arteriography has deemphasized the use and teaching to student and resident physicians of classic techniques to examine lower extremity pulses. Clinical evaluation and accurate pulse examination may eliminate the need for these often unnecessary and expensive tests to evaluate arterial insufficiency. In this report, we describe our technique for precise lower extremity pulse examination to teach younger physicians and remind more experienced ones of the value and necessity of this critical aspect of a physical examination.
Topics: Humans; Lower Extremity; Magnetic Resonance Angiography; Arteries; Computed Tomography Angiography; Arterial Occlusive Diseases
PubMed: 36633544
DOI: 10.23736/S0392-9590.22.04961-6 -
European Radiology Apr 2022
Topics: Angiography; Cerebral Angiography; Cerebrovascular Trauma; Computed Tomography Angiography; Humans; Retrospective Studies; Tomography, X-Ray Computed; Wounds, Nonpenetrating
PubMed: 35092475
DOI: 10.1007/s00330-021-08534-0 -
Journal of Vascular and Interventional... Dec 2019To characterize angiographic and cross-sectional imaging anatomy of the rat visceral vasculature in 2 translational models.
PURPOSE
To characterize angiographic and cross-sectional imaging anatomy of the rat visceral vasculature in 2 translational models.
MATERIALS AND METHODS
Animal studies were conducted in accordance with institutional guidelines and approval of the Institutional Animal Care and Use Committees. Retrospective review of digital subtraction arteriography was performed in 65 Wistar and 50 Sprague-Dawley male rats through a left common carotid artery or right common femoral artery approach. MR imaging of the abdomen was performed on the rats to correlate imaging modalities.
RESULTS
Aortography was performed in 3 locations, including cranial to the celiac artery, cranial to the renal arteries, and cranial to the caudal (inferior) mesenteric artery, enabling characterization of the visceral branch arteries in all 65 Wistar rats. Selective arteriography of first-, second-, and third-order branch vessels of the aorta was performed allowing characterization of normal and variant anatomy. Dedicated selective arteriography was performed of the celiac artery in 65 Wistar and 10 Sprague-Dawley rats, of the common hepatic artery in 65 Wistar and 50 Sprague-Dawley rats, and of the cranial mesenteric artery in 43 Wistar rats. MR imaging enabled correlation with the lobar and portal venous anatomy.
CONCLUSIONS
Analysis of arteriography and MR imaging in these rat models will provide translational researchers with anatomic details needed to develop new endovascular protocols for small animal research in interventional radiology.
Topics: Angiography, Digital Subtraction; Animals; Aorta; Aortography; Celiac Artery; Magnetic Resonance Angiography; Male; Models, Animal; Portal Vein; Predictive Value of Tests; Rats, Sprague-Dawley; Rats, Wistar; Retrospective Studies; Translational Research, Biomedical; Viscera
PubMed: 31202678
DOI: 10.1016/j.jvir.2019.03.005