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Developments in Ophthalmology 2016Optovue AngioVue system technology for optical coherence tomography (OCT) angiography is based on the AngioVue Imaging System (Optovue, Inc., Freemont, CA), using... (Review)
Review
Optovue AngioVue system technology for optical coherence tomography (OCT) angiography is based on the AngioVue Imaging System (Optovue, Inc., Freemont, CA), using split-spectrum amplitude-decorrelation angiography (SSADA) algorithm. This algorithm was developed to minimize scanning time. It detects motion in blood vessel lumen by measuring the variation in reflected OCT signal amplitude between consecutive cross-sectional scans. The novelty of SSADA lies in how the OCT signal is processed to enhance flow detection and reject axial bulk motion noise. Specifically, the algorithm splits the OCT image into different spectral bands, thus increasing the number of usable image frames. Each new frame has a lower axial resolution that is less susceptible to axial eye motion caused by blood pulsation. Optovue AngioVue system technology allows quantitative analysis. It provides numerical data about flow area and non-flow area. It can also generate a flow density map. These metrics may serve as biomarkers in diagnosis and for tracking disease progression or treatment response. Flow area: the software will calculate the drawn area and vessel area in mm(2). It allows for comparison of all measurements for a given participant. Non-flow area: the software shows the non-perfused areas by mouse click selection. Ischemic areas will be shown in yellow. These areas may be saved and matched with others in the study. Flow density tool is able to measure the percentage of vascular areas on en face angiograms. This analysis is based on an ETDRS grid centered on the macula as with the thickness map. This tool works both on inner and outer vascular plexus.
Topics: Angiography; Animals; Choroid; Diagnostic Techniques, Ophthalmological; Fluorescein Angiography; Humans; Retinal Vessels; Tomography, Optical Coherence
PubMed: 27022989
DOI: 10.1159/000442770 -
Klinische Monatsblatter Fur... Sep 2017Optical coherence tomography angiography (OCTA) provides, non-invasively, a three-dimensional visualization of the microvasculature of the retina and choroid. However,... (Comparative Study)
Comparative Study Review
Optical coherence tomography angiography (OCTA) provides, non-invasively, a three-dimensional visualization of the microvasculature of the retina and choroid. However, image artifacts may occur in OCTA and have an impact on clinical interpretation. The aim of this article is to describe image artifacts of OCTA and to present a nomenclature. OCTA examinations were performed with the AngioPlex OCTA-technology in combination with the CIRRUS HD-OCT 5000 (Carl Zeiss Meditec, Inc., Dublin, USA) as well as with the PlexElite 9000 (Carl Zeiss Meditec, Inc., Dublin, USA). Typical artifacts identified in the OCTA images are described and their causes are explained. There are three main groups of artifacts that can be distinguished: (a) artifacts that are inherent in the OCTA technology and occur with all types of devices (projection artifacts, masking, unmasking, loss of signal); (b) artifacts caused by data and image processing algorithms and whose frequency or severity may depend on the device type used (segmentation artifacts, duplications of vessels); (c) motion artifacts that vary in frequency and severity depending on the type of device used, as different methods (e.g., eye tracker) are used to reduce them. The occurrence of artifacts is also dependent on patient cooperation, the clarity of the optical media, and the pathology of the retina. As in any other imaging method, artifacts also occur in OCTA images. Nevertheless, qualitative assessment of OCTA images is almost always possible and provides indispensable findings on the morphology and perfusion status of the retina and choroid. A good knowledge of possible artifacts, and a critical analysis of the complete OCTA data set, allows a correct interpretation and is essential for making a precise clinical diagnosis.
Topics: Angiography; Artifacts; Choroid Diseases; Diagnosis, Differential; Equipment Design; Humans; Retinal Diseases; Risk Factors; Tomography, Optical Coherence
PubMed: 28628928
DOI: 10.1055/s-0043-112857 -
Circulation Journal : Official Journal... Apr 2022
Topics: Angiography; Contrast Media; Coronary Angiography; Female; Humans; Male; Renal Insufficiency, Chronic
PubMed: 35354716
DOI: 10.1253/circj.CJ-22-0141 -
Optics Letters Oct 2022A fast and practical computational cross-calibration of multiple spectrometers is described. A signal correlation matrix (CM) can be constructed from paired B-scans in a...
A fast and practical computational cross-calibration of multiple spectrometers is described. A signal correlation matrix (CM) can be constructed from paired B-scans in a multiple-spectrometer optical coherence tomography (OCT), where the wavelength-corresponding pixels are indicated by high cross correlation. The CM can be used to either guide the physical alignment of spectrometers or to numerically match the spectra in the post-process. The performance is comparable to the previously reported optimization approach, as demonstrated by the mirror tests, qualitative comparison of OCT and optical coherence tomography angiography (OCTA) images, and quantitative comparison of image metrics.
Topics: Angiography; Calibration; Fluorescein Angiography; Refractometry; Tomography, Optical Coherence
PubMed: 36181195
DOI: 10.1364/OL.468707 -
The Veterinary Clinics of North... May 2022As part of the cardiovascular examination, all birds underwent clinical and echocardiographic examinations. Radiographs and blood samples were taken. Each bird was... (Review)
Review
As part of the cardiovascular examination, all birds underwent clinical and echocardiographic examinations. Radiographs and blood samples were taken. Each bird was premedicated with midazolam and medetomidin and anesthetized with inhalation anesthesia using isoflurane. We performed computed tomographic angiography (CTA) after intravenous injection of 1 to 2 mL contrast agent per kg followed by a 1 mL saline solution flush. We were been able to identify the arteries that previous studies revealed to be most likely affected by atherosclerotic lesions: the aorta, both pulmonary arteries, and both brachiocephalic trunks. CTA was safe and is of potential diagnostic value in birds.
Topics: Angiography; Animals; Birds; Contrast Media; Tomography, X-Ray Computed
PubMed: 35422261
DOI: 10.1016/j.cvex.2022.01.008 -
Plastic and Reconstructive Surgery Feb 2016Evolving intraoperative technology has an increased presence and usefulness in aiding surgeon clinical judgment. Many surgical devices are readily available as an... (Review)
Review
Evolving intraoperative technology has an increased presence and usefulness in aiding surgeon clinical judgment. Many surgical devices are readily available as an adjunct to this gold standard assessment of adequate tissue perfusion. Intraoperative perfusion monitoring provides surgeons with the ability to interpret additional information that enhances surgical decision-making in real-time. Technologies include various dye-based and non-dye-based near-infrared angiography, tissue oximetry measurements, and ultrasound-based tools. This review summarizes the available intraoperative technologies for planning and assessment of tissue perfusion in plastic and reconstructive surgery. The authors discuss the available literature for the individual devices and supporting evidence for their use. The authors recommend the evidence-based use of these tools in indicated surgical cases to improve clinical outcomes.
Topics: Angiography; Humans; Indocyanine Green; Monitoring, Intraoperative; Plastic Surgery Procedures; Regional Blood Flow
PubMed: 26818312
DOI: 10.1097/01.prs.0000475765.83901.80 -
Acta Neurologica Taiwanica Jun 2019ation. No significant past medical history except for pharmacologically controlled mild hypertension. During the neurological examination the patient appeared alert,...
ation. No significant past medical history except for pharmacologically controlled mild hypertension. During the neurological examination the patient appeared alert, oriented and showed no deficit of strength, sensitivity and coordination. An expressive temporary aphasia was confirmed and Transient Ischemic Attacks (TIA) was suspected. Cranial Computed Tomography Angiography (CTA) showed hypoplasia of left Internal Carotid Artery (ICA) with a focal duplication in the intracavernous segment (Figure 1, arrowhead). Circle of Willis appears to be regular, with the left middle cerebral artery supported by the vertebrobasilar system through the left posterior communicating artery of increased caliber, and by the contralateral ICA via anterior communicating artery. Consequently, patient underwent Digital Subtraction Angiography (DSA) lateral view that confirmed the segmental duplication of the left intracavernous ICA (Figure 2, arrowhead). Vessels had a lightly winding course within the cavernous sinus and the intracranial branches downstream of their confluence presented a slight delay in visualization. After few hours her symptoms completely regressed and, in agreement with clinical and imaging data, diagnosis of TIA was made. The transient ischemic event was, in fact, most likely caused by low flow to the left cerebral hemisphere due to hypoplasia of the ICA and aforementioned abnormalities of its intracavernous tract that caused alteration and reduction of intracranial flow distribution. Medical treatment with anti-platelet drugs was started and patient was discharged with a clinical, laboratory and imaging follow-up program. Duplications of ICA in the intracranial tract are very rare(1,2). Most of the cases are localized in the supraclinoid segment. To our knowledge this is the first case described in literature of true duplication of ICA in the intracavernous tract. Patients with congenital variants or acquired pathology of ICA are mostly asymptomatic, but when symptoms appear, patients must be investigated(1-3). CTA is considered the first line non-invasive diagnostic method for intracranial vascular anatomy. At present, medical treatment remains the choice in patients with no-complicated duplications of ICA in the intracranial tract.
Topics: Angiography, Digital Subtraction; Carotid Artery, Internal; Cerebral Angiography; Computed Tomography Angiography; Female; Humans
PubMed: 31867708
DOI: No ID Found -
Sichuan Da Xue Xue Bao. Yi Xue Ban =... May 2022To evaluate the safety and effectiveness of transcatheter arterial embolization (TAE) in the treatment of acute non-variceal upper gastrointestinal bleeding (ANVUGIB),...
OBJECTIVE
To evaluate the safety and effectiveness of transcatheter arterial embolization (TAE) in the treatment of acute non-variceal upper gastrointestinal bleeding (ANVUGIB), and to guide clinical practice and continue to optimize diagnosis and treatment strategies.
METHODS
This retrospective study included 266 patients who underwent angiography due to ANVUGIB between March 2016 and March 2021. Data on the positive rate of angiography, the technical success rate and clinical success rate of TAE, and the rebleeding rate and the all-cause mortality within 30 days after TAE treatment were collected, and the influencing factors relevant to the above events were analyzed accordingly.
RESULTS
All 266 patients completed angiography--the positive rate of angiography was 54.1% (144/266), the total technical success rate was 97.3% (217/223), the clinical success rate was 73.1% (155/212), and the rebleeding rate and all-cause mortality within 30 days were 26.9% (57/212) and 16.1% (35/217), respectively. This study found that shock index>1 ( =5.950; 95% : 1.481-23.895; =0.012), computed tomography angiography (CTA) positive result ( =6.813; 95% : 1.643-28.252; =0.008) and interval<24 h ( =10.530; 95% : 2.845-38.976; <0.001) were independent predictors of positive angiography. Shock index>1 ( =2.544; 95% : 1.301-4.972; =0.006) and INR>1.5 ( =3.207; 95% : 1.381-7.451; =0.007) were independent risk factors for rebleeding. Patients with postoperative bleeding ( =3.174; 95% : 1.164-8.654; =0.024) and patients with rebleeding after embolization ( =34.665; 95% : 11.471-104.758; <0.001) had a higher risk of death within 30 days.
CONCLUSION
TAE is safe and effective in the treatment of ANVUGIB. Patients with shock index>1 and positive CTA are more likely to be angiographic positive, and should undergo angiography as early as possible after bleeding. In addition, rebleeding after embolization deserves high attention.
Topics: Acute Disease; Angiography; Embolization, Therapeutic; Gastrointestinal Hemorrhage; Humans; Retrospective Studies; Treatment Outcome
PubMed: 35642145
DOI: 10.12182/20220560203 -
Interventional Neuroradiology : Journal... Jun 2024Pure arterial malformations (PAMs) are rare vascular lesions often detected incidentally on brain imaging. They are characterised by a mass of arterial loops containing...
Pure arterial malformations (PAMs) are rare vascular lesions often detected incidentally on brain imaging. They are characterised by a mass of arterial loops containing arteries that are tortuous, overlapping and dilated without any associated arteriovenous shunting. The incidence of PAMs have been rising due to the increasing use of non-invasive angiographic imaging for the diagnosis of neurovascular disorders. This article will present the clinical course of two cases of PAM, both of which demonstrated a stable appearance on surveillance imaging despite the lack of surgical or endovascular intervention.
Topics: Humans; Cerebral Angiography; Female; Male; Adult; Angiography, Digital Subtraction; Magnetic Resonance Angiography; Intracranial Arteriovenous Malformations; Middle Aged; Magnetic Resonance Imaging
PubMed: 35892156
DOI: 10.1177/15910199221116006 -
European Radiology Jun 2022• TOF MRA is very important in the evaluation of cerebrovascular stenosis, and a novel evaluation system can further enhance its strengths.• This evaluation system...
• TOF MRA is very important in the evaluation of cerebrovascular stenosis, and a novel evaluation system can further enhance its strengths.• This evaluation system is more accurate based on the fact that cerebral vascular stenosis alters hemodynamics and leads to different imaging presentations.
Topics: Arteries; Cerebral Angiography; Constriction, Pathologic; Humans; Magnetic Resonance Angiography
PubMed: 35076760
DOI: 10.1007/s00330-021-08521-5