This document provides an overview of carotid Doppler ultrasound. It begins with the anatomy of the carotid arteries and their branches. It then discusses the technique of carotid Doppler ultrasound, including instrumentation, examination protocol, and interpretation of ultrasound findings. It provides details on evaluating the internal carotid, external carotid, and vertebral arteries for stenosis or occlusion. The document also covers characterizing carotid plaques and differentiating true findings from artifacts.
This document provides information on carotid Doppler ultrasound studies, including:
- Anatomy of the carotid arteries and branches
- Technique for performing carotid Doppler ultrasound exams, including patient positioning, transducer use, and Doppler settings
- Analysis of waveforms in normal carotid arteries versus arteries with disease
- Causes of carotid artery disease and common sites of extracranial arterial disease
- Characterization of carotid plaques based on echogenicity, morphology, and other properties.
A CT coronary angiogram (CTCA) uses computed tomography to non-invasively image the coronary arteries. It provides useful information about coronary artery disease. Specialists who interpret CTCAs must complete training requirements, including a minimum number of cases. CTCA is a low-risk, low-radiation exam that can accurately detect narrowings or anomalies in the coronary arteries. It may benefit those with suspected coronary artery disease, atypical chest pain, or to check grafts. Indications include chest pain with low-intermediate risk or family history. Preparation includes fasting and potentially taking a beta-blocker to lower the heart rate.
This document discusses cardiac MRI (CMRI) and its clinical applications. CMRI provides anatomical and functional information to assess heart abnormalities through various sequences like ECG-gated bright and dark blood sequences. It is useful for evaluating congenital heart diseases, valvular heart diseases, ventricular function, coronary arteries, myocardial perfusion and viability, cardiac masses, and pericardial diseases. CMRI is more accurate than echocardiography for measuring ejection fraction, volumes, and assessing ventricular function and viability. It is useful for differentiating conditions like arrhythmogenic right ventricular dysplasia, restrictive vs constrictive cardiomyopathy, and determining feasibility of revascularization procedures.
This document discusses the Doppler ultrasound assessment of the portal venous system. It begins with an overview of the sonographic and Doppler evaluation of the portal system's anatomy and normal circulation. It then covers the assessment of specific vessels like the portal vein, hepatic veins, and hepatic artery through grayscale ultrasound and Doppler evaluation. Key aspects like normal vessel diameters, waveforms, and flow direction are defined. The document concludes by outlining the important Doppler assessment techniques and parameters used to evaluate the portal system.
This document provides information on performing and interpreting renal Doppler ultrasounds. It discusses the optimal approaches for imaging the renal arteries, including the anterior, oblique, and flank approaches. It also outlines criteria for evaluating renal artery stenosis, including peak systolic velocity measurements and the renal-aortic ratio. Common renal pathologies that can be identified with Doppler ultrasound are also summarized, such as fibromuscular dysplasia, atherosclerosis, aneurysms, and hydronephrosis.
CT coronary angiography uses ECG gating to synchronize data acquisition with the cardiac cycle in order to reduce motion artifacts. Data can be acquired retrospectively by continuously scanning over multiple heartbeats and reconstructing different cardiac phases, or prospectively by only scanning during a targeted phase like mid-diastole. Placement of the ROI for bolus tracking is important to ensure consistent coronary enhancement. High temporal resolution under 200ms can be achieved through techniques like partial scan or multisegment reconstruction.
Presentation given at Arab Health congress on Jan. 29th 2013, with information about (dual source) Cardiac CT of the coronary arteries with technical & practical information and some clinical use cases
Carotid artery Doppler uses ultrasound to examine the carotid arteries in the neck. It can detect plaques, stenosis, dissections, and other abnormalities. A normal study shows the carotid bifurcation into the internal and external carotid arteries, with the internal carotid having low resistance flow and the external carotid having reduced diastolic flow. Doppler waveform analysis examines flow patterns to identify abnormalities. The test is used to evaluate risks of stroke and transient ischemic attacks.
This document provides information on carotid Doppler ultrasound studies, including:
- Anatomy of the carotid arteries and branches
- Technique for performing carotid Doppler ultrasound exams, including patient positioning, transducer use, and Doppler settings
- Analysis of waveforms in normal carotid arteries versus arteries with disease
- Causes of carotid artery disease and common sites of extracranial arterial disease
- Characterization of carotid plaques based on echogenicity, morphology, and other properties.
A CT coronary angiogram (CTCA) uses computed tomography to non-invasively image the coronary arteries. It provides useful information about coronary artery disease. Specialists who interpret CTCAs must complete training requirements, including a minimum number of cases. CTCA is a low-risk, low-radiation exam that can accurately detect narrowings or anomalies in the coronary arteries. It may benefit those with suspected coronary artery disease, atypical chest pain, or to check grafts. Indications include chest pain with low-intermediate risk or family history. Preparation includes fasting and potentially taking a beta-blocker to lower the heart rate.
This document discusses cardiac MRI (CMRI) and its clinical applications. CMRI provides anatomical and functional information to assess heart abnormalities through various sequences like ECG-gated bright and dark blood sequences. It is useful for evaluating congenital heart diseases, valvular heart diseases, ventricular function, coronary arteries, myocardial perfusion and viability, cardiac masses, and pericardial diseases. CMRI is more accurate than echocardiography for measuring ejection fraction, volumes, and assessing ventricular function and viability. It is useful for differentiating conditions like arrhythmogenic right ventricular dysplasia, restrictive vs constrictive cardiomyopathy, and determining feasibility of revascularization procedures.
This document discusses the Doppler ultrasound assessment of the portal venous system. It begins with an overview of the sonographic and Doppler evaluation of the portal system's anatomy and normal circulation. It then covers the assessment of specific vessels like the portal vein, hepatic veins, and hepatic artery through grayscale ultrasound and Doppler evaluation. Key aspects like normal vessel diameters, waveforms, and flow direction are defined. The document concludes by outlining the important Doppler assessment techniques and parameters used to evaluate the portal system.
This document provides information on performing and interpreting renal Doppler ultrasounds. It discusses the optimal approaches for imaging the renal arteries, including the anterior, oblique, and flank approaches. It also outlines criteria for evaluating renal artery stenosis, including peak systolic velocity measurements and the renal-aortic ratio. Common renal pathologies that can be identified with Doppler ultrasound are also summarized, such as fibromuscular dysplasia, atherosclerosis, aneurysms, and hydronephrosis.
CT coronary angiography uses ECG gating to synchronize data acquisition with the cardiac cycle in order to reduce motion artifacts. Data can be acquired retrospectively by continuously scanning over multiple heartbeats and reconstructing different cardiac phases, or prospectively by only scanning during a targeted phase like mid-diastole. Placement of the ROI for bolus tracking is important to ensure consistent coronary enhancement. High temporal resolution under 200ms can be achieved through techniques like partial scan or multisegment reconstruction.
Presentation given at Arab Health congress on Jan. 29th 2013, with information about (dual source) Cardiac CT of the coronary arteries with technical & practical information and some clinical use cases
Carotid artery Doppler uses ultrasound to examine the carotid arteries in the neck. It can detect plaques, stenosis, dissections, and other abnormalities. A normal study shows the carotid bifurcation into the internal and external carotid arteries, with the internal carotid having low resistance flow and the external carotid having reduced diastolic flow. Doppler waveform analysis examines flow patterns to identify abnormalities. The test is used to evaluate risks of stroke and transient ischemic attacks.
A detailed description of ct coronary angiography and calcium scoring with various aspects regarding the preparation, procedure, limitations and a short review regarding post CABG imaging.
This document discusses Doppler ultrasonography and the analysis of blood flow patterns. It contains the following key points:
1. Doppler spectroscopy provides a time-velocity waveform representing blood flow velocities during the cardiac cycle, showing how velocity and the number of reflecting red blood cells varies over time.
2. Normal vessels have characteristic flow patterns depending on their anatomy and the organ they supply. Widening of the spectral line and filling of the spectral window indicates high flow or small vessels.
3. Pseudoaneurysms are caused by a complete rupture of the artery wall. Doppler can detect the communicating channel showing a "to-and-fro" waveform as blood enters and leaves the pooling cavity.
4.
This document discusses Doppler ultrasound of the carotid arteries. It begins with an introduction describing how carotid artery disease can cause strokes and how ultrasound is used to diagnose stenosis to determine surgical candidates. It then describes the anatomy of the carotid arteries and outlines the normal ultrasound appearance. Key points of a carotid ultrasound exam are described including using grayscale, color Doppler, power Doppler and spectral analysis. Different types of carotid plaques are defined as well as how they appear ultrasonographically. Methods for evaluating stenosis and differentiating true from pseudo-spectral broadening are also covered.
Fundamentals of Vascular Ultrasound.
Looking at the basics of carotid, lower extremity arterial, renal, celiac, SMA studies, as well as touching on venous insufficiency. Part I of series.
This document discusses Doppler ultrasonography and the spectral waveforms used to analyze blood flow patterns in vessels. It provides details on:
- The Doppler spectrum which represents blood flow velocities over time on a graph with frequency on the vertical axis and time on the horizontal axis.
- Characteristics of normal flow patterns seen in major vessels and how they relate to vessel anatomy and organ function.
- Abnormal flow patterns seen in pseudoaneurysms and arteriovenous fistulas which involve damage to vessel walls. Specific waveform patterns are described that indicate these conditions.
This document provides an overview of cardiac MRI techniques including gradient echo sequences which provide cine images of heart motion and white blood, spin echo sequences which produce static black blood images, and phase contrast imaging which uses Doppler to visualize blood flow direction and velocity. Delayed enhancement imaging identifies areas of scar or fibrosis by their contrast uptake several minutes after injection. Other techniques discussed are perfusion imaging, tissue tagging, and STIR imaging for edema detection. Common imaging planes and protocols are outlined along with common uses of cardiac MRI such as assessing function, cardiomyopathy, and viability.
Doppler ultrasound of carotid arteriesSamir Haffar
This document discusses Doppler ultrasound of carotid arteries. It begins with the anatomy of carotid arteries and then discusses normal Doppler ultrasound findings of the carotid arteries including flow patterns and spectral waveforms. It describes various pathologies that can cause carotid artery disease such as atherosclerosis and other non-atherosclerotic diseases. It also discusses how diseases outside the carotid arteries can affect them. The document provides detailed information on ultrasound techniques for evaluating the carotid arteries and interpreting ultrasound findings for plaque characterization and grading stenosis.
1) Carotid Doppler ultrasound is used to evaluate the carotid arteries for stenosis or occlusion. It involves using grayscale, color Doppler, and spectral Doppler to examine the anatomy and flow of the carotid arteries.
2) A normal carotid Doppler ultrasound will show triphasic waveforms within the carotid arteries with velocities under 125 cm/sec. The intima-media thickness should be less than 0.8-0.9mm.
3) Carotid artery disease is most commonly caused by atherosclerosis which can be evaluated using Doppler ultrasound parameters like peak systolic velocity, end diastolic velocity, and ICA/CCA velocity ratios to grade the severity of stenosis.
1) MDCT provides detailed images of coronary artery anatomy and is useful for evaluating common coronary pathologies.
2) The coronary arteries normally arise from the sinuses of Valsalva and have variable branching patterns. MDCT helps distinguish benign variants from potentially dangerous anomalies.
3) Coronary artery anomalies can involve abnormal origins, courses, or terminations and in some cases may lead to ischemia or sudden cardiac death. MDCT is well-suited to characterize these anomalies.
Myocardial viability testing is important in patients with coronary disease and severely reduced left ventricular systolic function to determine whether revascularization may improve outcomes by identifying dysfunctional but still viable myocardium. Revascularization of viable myocardium can help recover function and symptoms, whereas predominantly scarred myocardium will not benefit from revascularization.
Peripheral angiography is a radiological procedure used to examine arteries and veins after injecting contrast media. It involves puncturing an artery such as the femoral artery using the Seldinger technique and threading a catheter over a guidewire to inject contrast media and obtain images. The procedure is used to diagnose and treat various vascular conditions. Precise positioning, sterile equipment and contrast injection are needed to obtain diagnostic images of the peripheral vasculature.
This document discusses various pathologies of the carotid arteries that can be detected using Doppler ultrasound. It begins by discussing non-arteriosclerotic diseases such as fibromuscular dysplasia, carotid and vertebral dissection, vasospasm, aneurysms, arterio-venous fistulas, and arteritis. It then focuses on the ultrasound appearance and diagnostic criteria for spontaneous carotid and vertebral dissection. The document also reviews limitations of carotid ultrasound examinations and advantages of power Doppler mode. Throughout it provides ultrasound images to illustrate the different pathologies.
Pulmonary Artery Anatomy and Pulmonary EmbolismGamal Agmy
The document describes the anatomy of the pulmonary arteries, including their branching patterns and variations. It begins with an overview of the main pulmonary artery and its bifurcation. It then details the typical anatomy and variations seen in the arteries of the right upper lobe, middle lobe, right lower lobe, left upper lobe, and left lower lobe. Key branches are named according to accepted anatomical conventions. Variations that occur in 10-30% of individuals are highlighted.
This document discusses computed tomography angiography (CTA) and its applications in cardiology. CTA uses computed tomography to visualize blood vessels throughout the body, including coronary arteries. Coronary CTA can detect plaque buildup in coronary arteries without being invasive. Current multidetector CT systems can acquire high-resolution images of the heart within 20 seconds while the patient holds their breath. Coronary CTA provides diagnostic information but also exposes patients to radiation. It is most useful for evaluating cardiac symptoms in low-to-intermediate risk patients.
Presentation1.pptx, radiological imaging of lower limb ischemia.Abdellah Nazeer
This document discusses radiological imaging techniques for evaluating lower limb ischemia. It provides details on:
1. The definitions and classifications of acute versus chronic limb ischemia and their common etiologies such as embolism and thrombosis.
2. The imaging options for evaluating limb ischemia including digital subtraction angiography (DSA), duplex ultrasonography, CT angiography (CTA), and MR angiography (MRA) along with the advantages and disadvantages of each technique.
3. Examples of imaging findings in limb ischemia including occlusion sites and presence of collaterals. Imaging plays a key role in diagnosing the etiology and guiding treatment of lower limb ischemia.
This document provides an overview of performing a normal carotid artery Doppler study. It discusses the anatomy of the carotid arteries and examines protocol, including using high-frequency transducers, color Doppler, and analyzing Doppler spectral waveforms. The appearance of normal carotid artery walls and blood flow characteristics are described. Tips are provided for differentiating the external and internal carotid arteries. The document references sources for further information on vascular ultrasonography techniques and carotid artery anatomy.
The document discusses the various types of congenital anomalies of the inferior vena cava that can occur during embryonic development. It describes 9 types of anomalies and provides diagrams to illustrate them. The anomalies result from variations in the regression of the embryonic posterior cardinal, subcardinal, and supracardinal veins that normally form the segments of the inferior vena cava. The document also provides details on the embryonic development of the normal inferior vena cava and how variations can lead to anomalous structures.
Ultrasound can be used to examine the extracranial arteries that supply blood to the brain. Pathology in these arteries can lead to stroke. A carotid ultrasound exam should image and measure blood flow in the carotid and vertebral arteries bilaterally and evaluate any lesions found. Ultrasound is a noninvasive way to detect pathology in the extracranial arteries that may cause stroke.
This document discusses Doppler ultrasound in peripheral arterial disease. It begins by explaining Doppler ultrasound waveforms and how they relate to blood flow direction and velocity. It then covers topics like antegrade versus retrograde flow, pulsatile versus nonpulsatile flow, and directionality. The document also discusses spectral broadening and differentiating high- versus low-resistance arteries. It provides diagrams to illustrate topics like stenosis, collateral flow, and the definitions of upstream and downstream. Finally, it outlines the criteria for classifying and grading peripheral arterial stenosis using Doppler ultrasound.
A 60-year-old male presented with giddiness, vertigo, and a history of hypertension, chest pain, and prior CABG surgery. Examination found carotid bruits bilaterally. Carotid Doppler was ordered to evaluate for possible carotid artery disease or posterior circulation abnormality.
Carotid Doppler involves B-mode, color Doppler, and spectral Doppler analyses of the carotid arteries. Spectral Doppler provides information on flow patterns, velocities, and pulsatility which can identify stenosis or occlusion. Plaque characterization evaluates composition and risk of embolism. Carotid Doppler is useful for evaluating TIAs, bruits, known disease, and pre-operative screening.
The Doppler examination as
Carotid ultrasound is used to detect plaque buildup in the carotid arteries, which can harden or rupture over time and increase the risk of stroke. Plaque can narrow the arteries and reduce blood flow to the brain. Ruptured plaque can also form blood clots, which may block or partially block the carotid artery and cause a stroke if pieces of plaque or clots break off and travel to the brain. Carotid ultrasound is recommended for those who have had a stroke or mini-stroke, have an abnormal carotid bruit sound, blood clots in the carotid arteries, or a dissection in the carotid artery wall. Ultrasound images show normal versus abnormal carotid arteries, including plaque buildup, ulcerations
A detailed description of ct coronary angiography and calcium scoring with various aspects regarding the preparation, procedure, limitations and a short review regarding post CABG imaging.
This document discusses Doppler ultrasonography and the analysis of blood flow patterns. It contains the following key points:
1. Doppler spectroscopy provides a time-velocity waveform representing blood flow velocities during the cardiac cycle, showing how velocity and the number of reflecting red blood cells varies over time.
2. Normal vessels have characteristic flow patterns depending on their anatomy and the organ they supply. Widening of the spectral line and filling of the spectral window indicates high flow or small vessels.
3. Pseudoaneurysms are caused by a complete rupture of the artery wall. Doppler can detect the communicating channel showing a "to-and-fro" waveform as blood enters and leaves the pooling cavity.
4.
This document discusses Doppler ultrasound of the carotid arteries. It begins with an introduction describing how carotid artery disease can cause strokes and how ultrasound is used to diagnose stenosis to determine surgical candidates. It then describes the anatomy of the carotid arteries and outlines the normal ultrasound appearance. Key points of a carotid ultrasound exam are described including using grayscale, color Doppler, power Doppler and spectral analysis. Different types of carotid plaques are defined as well as how they appear ultrasonographically. Methods for evaluating stenosis and differentiating true from pseudo-spectral broadening are also covered.
Fundamentals of Vascular Ultrasound.
Looking at the basics of carotid, lower extremity arterial, renal, celiac, SMA studies, as well as touching on venous insufficiency. Part I of series.
This document discusses Doppler ultrasonography and the spectral waveforms used to analyze blood flow patterns in vessels. It provides details on:
- The Doppler spectrum which represents blood flow velocities over time on a graph with frequency on the vertical axis and time on the horizontal axis.
- Characteristics of normal flow patterns seen in major vessels and how they relate to vessel anatomy and organ function.
- Abnormal flow patterns seen in pseudoaneurysms and arteriovenous fistulas which involve damage to vessel walls. Specific waveform patterns are described that indicate these conditions.
This document provides an overview of cardiac MRI techniques including gradient echo sequences which provide cine images of heart motion and white blood, spin echo sequences which produce static black blood images, and phase contrast imaging which uses Doppler to visualize blood flow direction and velocity. Delayed enhancement imaging identifies areas of scar or fibrosis by their contrast uptake several minutes after injection. Other techniques discussed are perfusion imaging, tissue tagging, and STIR imaging for edema detection. Common imaging planes and protocols are outlined along with common uses of cardiac MRI such as assessing function, cardiomyopathy, and viability.
Doppler ultrasound of carotid arteriesSamir Haffar
This document discusses Doppler ultrasound of carotid arteries. It begins with the anatomy of carotid arteries and then discusses normal Doppler ultrasound findings of the carotid arteries including flow patterns and spectral waveforms. It describes various pathologies that can cause carotid artery disease such as atherosclerosis and other non-atherosclerotic diseases. It also discusses how diseases outside the carotid arteries can affect them. The document provides detailed information on ultrasound techniques for evaluating the carotid arteries and interpreting ultrasound findings for plaque characterization and grading stenosis.
1) Carotid Doppler ultrasound is used to evaluate the carotid arteries for stenosis or occlusion. It involves using grayscale, color Doppler, and spectral Doppler to examine the anatomy and flow of the carotid arteries.
2) A normal carotid Doppler ultrasound will show triphasic waveforms within the carotid arteries with velocities under 125 cm/sec. The intima-media thickness should be less than 0.8-0.9mm.
3) Carotid artery disease is most commonly caused by atherosclerosis which can be evaluated using Doppler ultrasound parameters like peak systolic velocity, end diastolic velocity, and ICA/CCA velocity ratios to grade the severity of stenosis.
1) MDCT provides detailed images of coronary artery anatomy and is useful for evaluating common coronary pathologies.
2) The coronary arteries normally arise from the sinuses of Valsalva and have variable branching patterns. MDCT helps distinguish benign variants from potentially dangerous anomalies.
3) Coronary artery anomalies can involve abnormal origins, courses, or terminations and in some cases may lead to ischemia or sudden cardiac death. MDCT is well-suited to characterize these anomalies.
Myocardial viability testing is important in patients with coronary disease and severely reduced left ventricular systolic function to determine whether revascularization may improve outcomes by identifying dysfunctional but still viable myocardium. Revascularization of viable myocardium can help recover function and symptoms, whereas predominantly scarred myocardium will not benefit from revascularization.
Peripheral angiography is a radiological procedure used to examine arteries and veins after injecting contrast media. It involves puncturing an artery such as the femoral artery using the Seldinger technique and threading a catheter over a guidewire to inject contrast media and obtain images. The procedure is used to diagnose and treat various vascular conditions. Precise positioning, sterile equipment and contrast injection are needed to obtain diagnostic images of the peripheral vasculature.
This document discusses various pathologies of the carotid arteries that can be detected using Doppler ultrasound. It begins by discussing non-arteriosclerotic diseases such as fibromuscular dysplasia, carotid and vertebral dissection, vasospasm, aneurysms, arterio-venous fistulas, and arteritis. It then focuses on the ultrasound appearance and diagnostic criteria for spontaneous carotid and vertebral dissection. The document also reviews limitations of carotid ultrasound examinations and advantages of power Doppler mode. Throughout it provides ultrasound images to illustrate the different pathologies.
Pulmonary Artery Anatomy and Pulmonary EmbolismGamal Agmy
The document describes the anatomy of the pulmonary arteries, including their branching patterns and variations. It begins with an overview of the main pulmonary artery and its bifurcation. It then details the typical anatomy and variations seen in the arteries of the right upper lobe, middle lobe, right lower lobe, left upper lobe, and left lower lobe. Key branches are named according to accepted anatomical conventions. Variations that occur in 10-30% of individuals are highlighted.
This document discusses computed tomography angiography (CTA) and its applications in cardiology. CTA uses computed tomography to visualize blood vessels throughout the body, including coronary arteries. Coronary CTA can detect plaque buildup in coronary arteries without being invasive. Current multidetector CT systems can acquire high-resolution images of the heart within 20 seconds while the patient holds their breath. Coronary CTA provides diagnostic information but also exposes patients to radiation. It is most useful for evaluating cardiac symptoms in low-to-intermediate risk patients.
Presentation1.pptx, radiological imaging of lower limb ischemia.Abdellah Nazeer
This document discusses radiological imaging techniques for evaluating lower limb ischemia. It provides details on:
1. The definitions and classifications of acute versus chronic limb ischemia and their common etiologies such as embolism and thrombosis.
2. The imaging options for evaluating limb ischemia including digital subtraction angiography (DSA), duplex ultrasonography, CT angiography (CTA), and MR angiography (MRA) along with the advantages and disadvantages of each technique.
3. Examples of imaging findings in limb ischemia including occlusion sites and presence of collaterals. Imaging plays a key role in diagnosing the etiology and guiding treatment of lower limb ischemia.
This document provides an overview of performing a normal carotid artery Doppler study. It discusses the anatomy of the carotid arteries and examines protocol, including using high-frequency transducers, color Doppler, and analyzing Doppler spectral waveforms. The appearance of normal carotid artery walls and blood flow characteristics are described. Tips are provided for differentiating the external and internal carotid arteries. The document references sources for further information on vascular ultrasonography techniques and carotid artery anatomy.
The document discusses the various types of congenital anomalies of the inferior vena cava that can occur during embryonic development. It describes 9 types of anomalies and provides diagrams to illustrate them. The anomalies result from variations in the regression of the embryonic posterior cardinal, subcardinal, and supracardinal veins that normally form the segments of the inferior vena cava. The document also provides details on the embryonic development of the normal inferior vena cava and how variations can lead to anomalous structures.
Ultrasound can be used to examine the extracranial arteries that supply blood to the brain. Pathology in these arteries can lead to stroke. A carotid ultrasound exam should image and measure blood flow in the carotid and vertebral arteries bilaterally and evaluate any lesions found. Ultrasound is a noninvasive way to detect pathology in the extracranial arteries that may cause stroke.
This document discusses Doppler ultrasound in peripheral arterial disease. It begins by explaining Doppler ultrasound waveforms and how they relate to blood flow direction and velocity. It then covers topics like antegrade versus retrograde flow, pulsatile versus nonpulsatile flow, and directionality. The document also discusses spectral broadening and differentiating high- versus low-resistance arteries. It provides diagrams to illustrate topics like stenosis, collateral flow, and the definitions of upstream and downstream. Finally, it outlines the criteria for classifying and grading peripheral arterial stenosis using Doppler ultrasound.
A 60-year-old male presented with giddiness, vertigo, and a history of hypertension, chest pain, and prior CABG surgery. Examination found carotid bruits bilaterally. Carotid Doppler was ordered to evaluate for possible carotid artery disease or posterior circulation abnormality.
Carotid Doppler involves B-mode, color Doppler, and spectral Doppler analyses of the carotid arteries. Spectral Doppler provides information on flow patterns, velocities, and pulsatility which can identify stenosis or occlusion. Plaque characterization evaluates composition and risk of embolism. Carotid Doppler is useful for evaluating TIAs, bruits, known disease, and pre-operative screening.
The Doppler examination as
Carotid ultrasound is used to detect plaque buildup in the carotid arteries, which can harden or rupture over time and increase the risk of stroke. Plaque can narrow the arteries and reduce blood flow to the brain. Ruptured plaque can also form blood clots, which may block or partially block the carotid artery and cause a stroke if pieces of plaque or clots break off and travel to the brain. Carotid ultrasound is recommended for those who have had a stroke or mini-stroke, have an abnormal carotid bruit sound, blood clots in the carotid arteries, or a dissection in the carotid artery wall. Ultrasound images show normal versus abnormal carotid arteries, including plaque buildup, ulcerations
Role of ct angiography in diagnosis of coronary anomalies GhadaSheta
CT angiography plays an important role in diagnosing coronary artery anomalies. It provides detailed 3D images of the coronary arteries with high spatial and temporal resolution in a noninvasive manner. Proper patient preparation including beta blockers to lower heart rate and nitroglycerin to dilate arteries is important for optimal imaging. CT angiography can detect various types of anomalies such as anomalous coronary artery origins, fistulas, myocardial bridging, and duplication of arteries. It serves as a roadmap for cardiologists in guiding patient management.
This document provides guidance on using ultrasound to assess the carotid arteries for atherosclerotic disease. It outlines the technical requirements, examination techniques, diagnostic criteria, and normal and abnormal findings. Doppler ultrasound is an accurate noninvasive method to diagnose high-grade carotid stenosis by measuring peak systolic velocities. Key findings include plaques that are hypoechoic or irregular in shape posing higher risk. Proper technique and accounting for vascular anomalies are important to avoid overestimating stenosis.
1. The document discusses the anatomy and epidemiology of carotid atherosclerotic disease. It describes the anatomy of the aortic arch and its branches, including the common, external, and internal carotid arteries.
2. Pathophysiology sections cover the development of atherosclerosis in the carotid bulb and mechanisms by which plaques can cause TIAs or strokes via embolization and hypoperfusion.
3. Evaluation and management are discussed, including use of carotid duplex ultrasound, CTA, MRA, and angiography to diagnose stenosis. Medical management focuses on risk factor modification including smoking cessation and diabetes control.
This document provides an overview of carotid artery ultrasound evaluation. It describes the normal anatomy of the carotid arteries and their branches. The protocol for a carotid ultrasound examination is outlined, including patient positioning, transducer selection, scanning sequences, and evaluation of stenosis. Key anatomical structures are defined, such as the intima-media complex. Non-atherosclerotic diseases that can involve the carotid or vertebral arteries, such as fibromuscular dysplasia, dissection, vasospasm, and aneurysms are also reviewed. The limitations of carotid ultrasound are noted.
coronary angiography, LV angiogram and coronary anomaliesSalman Ahmed
Coronary angiography is a procedure that uses dye and x-rays to visualize blood flow through the coronary arteries. It remains the gold standard for detecting significant coronary artery disease. The procedure involves passing a catheter into the heart and injecting contrast dye to see blockages. Coronary angiography is indicated when objective demonstration of the coronary anatomy could help resolve a problem, with competent staff and facilities. It provides information on stenosis levels and collateral circulation. Different views are used to visualize different coronary artery segments. Cannulation techniques depend on arterial origins and graft types.
Bedside Ultrasound in Neurosurgery Part 3/3Liew Boon Seng
Ultrasound can be used to assess intracranial dural arteriovenous fistulas (DAVF) and carotid cavernous fistulas (CCF). For DAVF, ultrasound shows increased velocities in feeding arteries and decreased resistance indices, allowing assessment before and after treatment. For CCF, ultrasound reveals abnormal mosaic flow in the cavernous sinus and engorged veins with reversed flow. It can monitor hemodynamic changes and treatment response in a noninvasive manner. Ultrasound is also useful for assessing cerebral veins and sinuses, and can diagnose temporal arteritis by identifying hypoechoic wall thickening and stenoses in temporal arteries.
This document discusses carotid Doppler ultrasound. It begins by outlining the anatomy of the carotid arteries and normal Doppler findings. It then discusses causes of carotid artery disease including atherosclerosis. Extra-carotid diseases that can affect the carotid arteries are also mentioned. The document provides detailed guidance on performing and interpreting carotid Doppler ultrasound scans including evaluating the intima-media thickness, flow patterns, spectral analysis, and grading stenosis. Imaging features of normal and diseased arteries are presented along with tips for accurate evaluation.
Transthoracic echocardiography in coronary artery diseaseangised
Transthoracic echocardiography can be used to visualize and assess coronary artery anatomy and physiology. Advances in imaging technology have improved visualization of non-dilated coronary arteries. The left anterior descending artery can often be seen in multiple windows. Coronary artery stenosis can be identified by detecting flow acceleration and turbulence. Coronary flow reserve testing provides prognostic information and can detect ischemia. Transthoracic echocardiography is a promising noninvasive tool for evaluating coronary artery disease.
The document provides information on performing carotid artery scanning, including vessel identification, recommended scanning protocols, waveform analysis, sample volume placement, and Doppler measurements. The key objectives are to identify the carotid and vertebral arteries, understand normal and abnormal waveforms, demonstrate proper techniques for sample volume placement, angle correction, and Doppler measurements like peak systolic velocity and end diastolic velocity. The document aims to educate ultrasound technicians on performing high quality carotid artery scans to evaluate for disease.
Bedside Ultrasound in Neurosurgery Part 2/3Liew Boon Seng
This document provides information from an ultrasound training course on various techniques for imaging intracranial vessels through different acoustic windows of the skull. It discusses techniques such as transorbital, temporal, and foramen magnum windows. It also covers topics like diagnosing intracranial occlusions and stenoses, grading carotid artery stenosis, diagnosing carotid dissections, assessing collateral flow, and evaluating bypass graft patency. The document discusses the use of transcranial Doppler in patients after decompressive craniectomy. It also reviews perfusion imaging with ultrasound contrast and experimental evidence for sonothrombolysis.
Coronary angiography is a procedure that uses dye and x-rays to see how blood flows through the coronary arteries of the heart. It is the gold standard for evaluating coronary artery disease and can identify the location and severity of any blockages. A coronary angiogram involves inserting a catheter into the heart and injecting dye so that blockages are highlighted on x-ray images. Potential complications are rare but can include heart attack, stroke, or kidney injury from the dye. The results of the angiogram are used to determine if further procedures like angioplasty or bypass surgery are needed.
Coronary angiography is a procedure that uses dye and x-rays to see how blood flows through the coronary arteries of the heart. It is the gold standard for evaluating coronary artery disease and can identify the location and severity of any blockages. A coronary angiogram involves inserting a catheter into the heart and injecting dye so that blockages are highlighted on x-ray images. Potential complications are usually minor but can include heart attack, stroke, or kidney injury from the dye. The results of the angiogram are used to determine if further procedures like angioplasty or bypass surgery are needed.
This document provides guidance on performing and interpreting coronary angiograms. It discusses techniques such as catheter selection, standard angiographic views, contrast injection settings, and complications. It also covers evaluating angiograms by quantifying lesions, classifying them using ACC/AHA criteria, and assessing TIMI flow. Interpretation involves a systematic analysis of the coronary anatomy and any areas of stenosis.
The document describes the anatomy of the carotid arteries and their branches, evaluation and imaging of carotid artery disease, and treatment strategies including lifestyle modifications to reduce risk factors, carotid endarterectomy to remove plaques from significantly stenotic arteries, and outcomes data from clinical trials on endarterectomy for symptomatic and asymptomatic carotid stenosis. Imaging modalities like carotid duplex ultrasound, CTA, and MRA are described for evaluating the degree of carotid stenosis. The benefits of carotid endarterectomy are greater for symptomatic high-grade stenosis while more moderate for asymptomatic disease.
The document provides an overview of coronary CT angiography (CCTA). It discusses recent advances in CCTA technology including perfusion imaging, spectral imaging, and fractional flow reserve CT (FFR-CT). The anatomy and physiology of the coronary arteries is described. The document outlines the equipment, indications, procedures, and post-processing techniques used in CCTA. It also discusses calcium scoring, artifacts, case studies, radiation dose, and limitations of CCTA.
Echo assessment of Aortic valve disease, Dr Ferdous assistant registrar, Card...Nizam Uddin
This document discusses the echocardiographic evaluation of aortic stenosis. It begins by describing normal aortic valve anatomy and various views used to visualize the aortic valve via 2D echocardiography. It then discusses the classification and causes of aortic stenosis, including calcific, rheumatic, and bicuspid aortic valve stenosis. Evaluation techniques covered include determining aortic valve area using the continuity equation and measuring transaortic jet velocity via continuous-wave Doppler. The document concludes by outlining the anatomical assessment of the aortic valve, methods for determining stenosis severity, and hemodynamic progression of untreated aortic stenosis over time.
Ultrasonography provides several advantages in clinical neurology. It can be used to assess neurovascular structures like arteries and veins, detect abnormalities associated with movement disorders like increased substantia nigra hyperechogenicity in Parkinson's disease, and evaluate peripheral nerves for entrapment neuropathies. Ultrasonography techniques like duplex ultrasonography and transcranial Doppler allow visualization of vessel structures, plaque composition, and blood flow velocities to diagnose vascular diseases, monitor treatment, and detect vasospasm. Transcranial Doppler is also used to evaluate movement disorders, cerebral circulation in stroke and brain injury, and support a diagnosis of brain death. Peripheral nerve ultrasonography examines cross-sectional area, echogenicity,
ABDOMINAL TRAUMA in pediatrics part one.drhasanrajab
Abdominal trauma in pediatrics refers to injuries or damage to the abdominal organs in children. It can occur due to various causes such as falls, motor vehicle accidents, sports-related injuries, and physical abuse. Children are more vulnerable to abdominal trauma due to their unique anatomical and physiological characteristics. Signs and symptoms include abdominal pain, tenderness, distension, vomiting, and signs of shock. Diagnosis involves physical examination, imaging studies, and laboratory tests. Management depends on the severity and may involve conservative treatment or surgical intervention. Prevention is crucial in reducing the incidence of abdominal trauma in children.
Does Over-Masturbation Contribute to Chronic Prostatitis.pptxwalterHu5
In some case, your chronic prostatitis may be related to over-masturbation. Generally, natural medicine Diuretic and Anti-inflammatory Pill can help mee get a cure.
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Basavarajeeyam is a Sreshta Sangraha grantha (Compiled book ), written by Neelkanta kotturu Basavaraja Virachita. It contains 25 Prakaranas, First 24 Chapters related to Rogas& 25th to Rasadravyas.
Rasamanikya is a excellent preparation in the field of Rasashastra, it is used in various Kushtha Roga, Shwasa, Vicharchika, Bhagandara, Vatarakta, and Phiranga Roga. In this article Preparation& Comparative analytical profile for both Formulationon i.e Rasamanikya prepared by Kushmanda swarasa & Churnodhaka Shodita Haratala. The study aims to provide insights into the comparative efficacy and analytical aspects of these formulations for enhanced therapeutic outcomes.
Integrating Ayurveda into Parkinson’s Management: A Holistic ApproachAyurveda ForAll
Explore the benefits of combining Ayurveda with conventional Parkinson's treatments. Learn how a holistic approach can manage symptoms, enhance well-being, and balance body energies. Discover the steps to safely integrate Ayurvedic practices into your Parkinson’s care plan, including expert guidance on diet, herbal remedies, and lifestyle modifications.
Basavarajeeyam is an important text for ayurvedic physician belonging to andhra pradehs. It is a popular compendium in various parts of our country as well as in andhra pradesh. The content of the text was presented in sanskrit and telugu language (Bilingual). One of the most famous book in ayurvedic pharmaceutics and therapeutics. This book contains 25 chapters called as prakaranas. Many rasaoushadis were explained, pioneer of dhatu druti, nadi pareeksha, mutra pareeksha etc. Belongs to the period of 15-16 century. New diseases like upadamsha, phiranga rogas are explained.
2. ANATOMY
Major branches of arch of aorta:
Innominate / brachiocephalic artery
Left common carotid artery
Left subclavian artery
3.
4. ANATOMY
Right and left common carotid arteries lie postero-laterally
to thyroid gland and deep to internal jugular vein and
sternocleidomastoid.
Right CCA originates at the bifurcation of brachiocephalic
artery.
Left CCA originated directly from arch of aorta and can
also arise with brachiocephalic trunk – Bovine
configuration.
7. CCA
The common carotid artery may be compressed against the
prominent transverse process of the sixth cervical vertebra
(carotid tubercle).
Above this level the artery is superficial and its pulsation
can be readily felt beneath the anterior border of
sternocleidomastoid.
9. ICA
The internal carotid arteries and their major branches (the
internal carotid system or anterior circulation) supply blood
to the majority of the forebrain.
The internal carotid artery arises from the bifurcation of the
common carotid artery, ascends in the neck and enters the
carotid canal of the temporal bone. Its course contains
Cervical, Petrous, Lacerum, Cavernous, Clinoid,
Ophthalmic & Communicating segments.
11. BRANCHES OF EXTERNAL
CAROTID
S: superior thyroid artery Sister
L: lingual artery Louis
P: posterior auricular artery Powdered
F: facial artery Face
O: occipital artery Often
A: ascending pharyngeal artery Attracts
M: maxillary artery Medical
S: superficial temporal artery Students
12. SURFACE ANATOMY
In the neck, the common carotid artery and its continuation,
the internal carotid artery may be represented by a straight
line from the sternoclavicular joint to a point just behind the
condyle of the mandible.
At the level of the upper border of the thyroid cartilage
(approximately at a level between the third and fourth
cervical vertebrae) the common carotid artery divides into
the external and internal carotid arteries.
13. INTRODUCTION
Ultrasound assessment of carotid arterial atherosclerotic
disease has become the first choice for carotid
artery screening, permitting the evaluation of both the
macroscopic appearance of plaques as well as flow
characteristics in the carotid artery.
14. CAROTID DUPLEX
B-mode and Doppler.
B-mode – grey scale, visualization of structures and
assessment of plaque morphology.
Hyperechoic
Hypoechoic
17. INDICATIONS
Patients scheduled for major cardiovascular surgery
Non-hemispheric / unexplained neurologic symptoms
Proven carotid disease
Carotid revascularization including stenting
Monitoring of vascular surgery
Suspected subclavian steal syndrome
19. INSTRUMENTATION
High frequency (5MHz or above) transducers with short
focal distances designed for near field work.
Colour Doppler imaging.
Duplex ultrasound with angle correction capabilities.
Doppler spectral waveform analysis.
Power Doppler imaging to assess low flow states and
possible occlusions.
20.
21.
22. CAROTID ULTRASOUND
EXAMINATION
Supine position.
Neck slightly extended.
Head turned away from site being examined.
5-12 MHz transducer for grey-scale.
3-7 MHz transducer for Doppler sonography.
5-10 MHz transducer for power Doppler.
23. TRANSDUCER POSITION
Several positions are used to examine the artery in long
axis(longitudinal) planes.
Selective short axis(transverse) views of carotid are
obtained from anterior, lateral, posterolateral approach .
Postero-lateral approach ,most useful for bifurcation &
distal ICA. The patient’s head should be turned far to contra
lateral side and transducer placed posterior to
sternocleidomastoid .
In some cases, anterolateral approach works best.
24. PROTOCOL
Vessels should be imaged as completely as possible
Caudal angulation of the transducer in the supra clavicular
region and cephalic angulation at the level of the mandible
Assessed both in grey scale and colour doppler settings.
Starting from proximal most CCA, bulb, ECA and ICA.
Distal carotid 2 cm from the bulb
31. CAROTID ULTRASOUND
INTERPRETATION
In most cases the gray-scale, color Doppler, and power
Doppler sonographic images and assessments will agree.
Disagreement – discover its source.
Grey scale and colour Doppler images better demonstrate
and quantify low-grade stenosis.
High-grade occlusive disease – more accurately defined by
Doppler spectral pattern.
33. ROLE OF POWER DOPPLER
Provides increased sensitivity to visualize the continuity of
blood flow in arterial stenosis.
Advantages:-
Angle independent
No aliasing
Very sensitive to low velocity and low amplitude flow
Helps in differentiating critical stenosis from occlusion
35. EXTERNAL CAROTID
Systolic upstroke is sharp
Spectral envelope is thin.
Reduced to no diastolic flow
Diastolic flow should be symmetrical bilaterally
Transient reversal in early diastole (characteristic early
diastolic notch ) ‐a normal finding
36.
37. INTERNAL CAROTID
Low‐resistance waveform pattern.
Systolic peak should be sharp and the spectral envelope
should be thin.
Continuous forward diastolic flow.
Systolic peak may be slightly blunter than the systolic peak
of the ECA.
38.
39. COMMON CAROTID
Combination of ICA and ECA patterns.
Intermediate amount of continuous forward diastolic flow
A sharp systolic upstroke and thin spectral envelope
Flow below the baseline or filling in of the spectral window
normally should not be seen
40.
41. CAROTID ULTRASOUND
ECA:
Feeds high resistance vascular bed.
Velocity rises sharply during systole.
Falls quickly during diastole.
42. CAROTID USG
ICA:
Feeds lower resistance brain circulation.
Large quantities of flow continue during diastole.
Velocity usually increase from proximal to distal.
CCA:
Resembles ICA waveform.
Diastolic flow above baseline.
43.
44.
45. CAROTID STENOSIS
Carotid artery stenosis also referred as extra cranial carotid
artery stenosis, is usually caused by an atherosclerotic
process and is one of the major causes
of stroke and transient ischemic attack (TIA).
The stenosis involving carotid bulb and the proximal
segment of ICA are the most common sites of
symptomatic and clinically relevant stenosis.
46. ABNORMAL CCA
either low or high PSVs.
abnormally high‐resistance waveform,
an abnormally low‐resistance waveform,
47. A normal CCA PSV should be in the range of 60 – 100 cm/s
IF less than this, examine opposite side
Symmetric ----------- > Low cardiac output
Asymmetric ------------ > Evaluate further
A velocity difference of >20 cm/sec between the right and left is
abnormal
49. ICA
Normal
ICA PSV is <125 cm/sec and no plaque or intimal thickening is
visible sonographically.
Additional criteria include ICA/CCA PSV ratio <2.0 and
ICA EDV <40 cm/sec
<50% ICA stenosis
ICA PSV is <125 cm/sec and plaque or intimal thickening is visible
sonographically.
Additional criteria include ICA/CCA PSV ratio <2.0 and
ICA EDV <40 cm/sec
50. 50-69% ICA stenosis
ICA PSV is 125-230 cm/sec and plaque is visible sonographically
additional criteria include ICA/CCA PSV ratio of 2.0-4.0 and ICA
EDV of 40-100 cm/sec
≥70% ICA stenosis but less than near occlusion
ICA PSV is >230 cm/sec and visible plaque and luminal narrowing
are seen at gray-scale and colour Doppler ultrasound
additional criteria include ICA/CCA PSV ratio >4 and ICA
EDV >100 cm/sec
51. Near occlusion of the ICA
Velocity parameters may not apply, since velocities may be high,
low, or undetectable.
Diagnosis is established primarily by demonstrating a markedly
narrowed lumen at colour or power Doppler ultrasound.
Total occlusion of the ICA:
No detectable patent lumen at gray-scale US and no flow with
spectral, power, and colour Doppler ultrasound.
There may be compensatory increased velocity in the contra lateral
carotid.
54. PLAQUE CHARACTERIZATION
Most common cause of TIA – embolism.
Important to identify low-grade atherosclerotic lesions
containing haemorrhage / ulceration.
Plaque – independent risk factor for developing stroke.
50-60 % of patients with hemispheric stroke symptoms
demonstrate hemorrhagic and ulcerated plaque.
55. PLAQUE TEXTURE
Homogenous plaque:
Uniform echopattern
Smooth surface
Sonolucency < 50% of plaque volume
Uniform acoustic texture corresponds to dense fibrous
connective tissue.
More common – 80-85% cases.
56.
57. PLAQUE TEXTURE
Heterogeneous plaque:
Complex echopattern
≥ 1 focal sonolucent areas corresponding > 50% of
plaque volume.
Contains intraplaque haemorrhage and deposits of
lipid, cholesterol and proteinaceous material.
Sensitivity – 90-94%
Specificity – 75-88%
58. PLAQUE MORPHOLOGY BASED
ON ULTRASOUND
Type 1 Predominantly echolucent
with thin echogenic cap.
Type 2 Substantially echolucent with
small areas of echogenicity
(>50% sonolucent).
Type 3 Predominantly echogenic
with small areas of
echoluceny (<50%
sonolucent).
Type 4 Uniformly echogenic.
59. TYPE 1 & 2 PLAQUES
Similar to heterogeneous plaque.
More likely to be associated with intraplaque haemorrhage
with ulceration.
Unstable and subject to abrupt changes in size after
haemorrhage / embolization.
Typically in symptomatic patients with stenosis > 70 % of
diameter.
60.
61.
62. TYPE 3 & 4 PLAQUES
Similar to homogeneous plaque.
Benign and stable.
Composed of fibrous tissue and calcification.
Typically seen in asymptomatic patients.
63.
64.
65. PLAQUE ULCERATION
All ulcerated plaques which can be accurately identified fit
into heterogeneous pattern.
USG findings:
Focal depression or break in plaque surface.
Anechoic region within plaque extending to vessel lumen.
Eddies of colour within plaque.
66.
67.
68.
69. POTENTIAL PITFALL IN
DIAGNOSIS
Mirror imaging artefact producing pseudo-ulceration of
carotid artery.
Highly reflective plaque can produce color doppler ghost
artefact simulating ulceration.
Region of color within the plaque can be recognised as
artefactual.
70. PITFALLS IN DIAGNOSIS
Spectral waveform and color shading within the pseudo-
ulceration are of lower amplitude, but otherwise identical to
those within the true carotid lumen.
Pulsed Doppler traces from within ulcer craters show low-
velocity damped waveforms.
71. VERTEBRALARTERY
Variations in origin are common.
Usually first branch of subclavian artery.
6-8 % - directly from the aortic arch.
90% - proximal vertebral artery ascends superomedially,
entering transverse foramen at C6 level.
72. VERTEBRALARTERY
42% - left larger than right.
26% - equal size on both sides.
32% - right larger than left.
Join at their confluence to form the basilar artery.
73.
74. VERTEBRALARTERY
Supplies majority of posterior circulation of brain.
Collateral circulation to other parts in carotid occlusive
disease.
Has a low resistance flow pattern similar to CCA with
continuous systole and diastole.
Because of small size, flow tends to demonstrate broader
spectrum.
75. SEGMENTS OF VERTEBRAL
ARTERY
V1 (preforaminal)
V2 (foraminal)
V3 (atlantic, extradural or extraspinal)
V4 (intradural or intracranial).
76.
77. VERTEBRAL WAVEFORM
Low resistance wave pattern
Forward diastolic flow
No systolic or diastolic notch
Similar to carotid in flow (colour)
No reversal of wave form
80. SUBCLAVIAN STEAL SYNDROME
Occurs when there is high grade stenosis or occlusion of the
proximal subclavian or innominate arteries with patent
vertebral arteries bilaterally.
Artery of ischemic limb steals blood from vertebrobasilar
circulation through retrograde vertebral artery flow, which
amy result in symptoms of vertebrobasilar insufficiency.
81.
82.
83. SUBCLAVIAN STEAL SYNDROME
Symptoms more pronounced during exercise of upper
extremity.
Also known as subclavian steal steno-occlusive disease.
85. STAGES
Reduced anterograde vertebral flow (stage I)
Reversal of flow during reactive hyperemia testing of the
arm (stage II)
Permanent retrograde vertebral flow (stage III).
86. INCOMPLETE/PARTIAL
SUBCLAVIAN STEAL
Transient reversal of vertebral artery flow during systole.
Maybe converted to complete steal using provocative
manoeuvres.
Suggestive of high grade stenotic lesion of subclavian
artery rather than occlusion.
87.
88. INCOMPLETE SUBCLAVIAN
STEAL
Provocative manoeuvres such as exercising the arm for 5
minutes or 5 minute inflation of sphygmomanometer on the
arm to induce rebound hyperaemia on the side of subclavian
lesion can enhance sonographic findings and convert an
incomplete steal to complete.
89.
90. PRESTEAL PHENOMENON
Anterograde flow but with a striking deceleration of
velocity in peak systole to a level less than EDV.
In patients with proximal subclavian stenosis.
Can be converted to partial or complete steal waveform by
provocative manoeuvres.
92. STENOSIS AND OCCLUSION
Most hemodynamically significant stenosis occurs at
vertebral artery origin.
Accurate velocity measurement difficult because of deep
location and tortuosity.
Velocities > 100 cm/s often indicate stenosis.
93. STENOSIS AND OCCLUSION
Focal increase in velocity of at least 50% visible stenosis or
striking tardus-parvus waveform indicates significant
vertebral stenosis.
Right and left common carotid arteries ascend into the neck and lie……
Bifurcation into right CCA and right subclavian artery.
Bovine configuration of aortic arch (more frequent variant on the left and less frequent variant on the right).
Bifurcation – cca into ext and int carotid arteries.
External carotid supplies facial musculature and has multiple branches in the neck
A VIP'S COMMA.
Patient in supine or semisupine position.
Head hyperextended and rotated 45 degree away from the side being examined.
Some perform at patient side and some prefer to sit at patient head.
Carotid sonographic anatomy. A, Transverse image of the left carotid bifurcation. The larger, more lateral vessel
is the internal carotid artery (I); E, external carotid artery
Color Doppler shows normal flow separation (arrow) in the proximal internal
carotid artery.
Carotid bifurcation. Longitudinal image
demonstrates common carotid artery (C); external carotid artery
(E); and large, posterior internal carotid artery (I).
Normal external carotid artery (ECA). A, Color Doppler ultrasound of bifurcation demonstrates two small
arteries originating from the ECA.
ECA spectral Doppler shows the anticipated serrated (sawtooth) flow disturbance from the temporal
artery tap (TT).
A
useful method to identify the ECA is the tapping of the
superficial temporal artery in the preauricular area, the
temporal tap (TT). The pulsations are transmitted back
to the ECA, where they cause a sawtooth appearance on
the spectral waveform (Fig. 25-4, B). Although the tap
helps identify the ECA, this tap deflection may be transmitted
into the CCA and even the ICA in certain rare
situations.
A, Right ECA shows a sharp systolic upstroke and relatively low-velocity end diastolic flow (arrow),
indicating a vessel supplying high-impedance circulation.
B, ICA shows a larger amount of end diastolic flow consistent with the lowimpedance
intracerebral circulation. Angle theta (arrow) is 50 degrees
C, Normal distal CCA waveform is a composite of low-resistance
ICA and higher-resistance CCA waveforms. Note that flow in C is toward the transducer (arrow) and the Doppler spectrum is plotted
above the baseline. In A and B, flow is directed away from the transducer. Although these spectra have been inverted, the negative velocity
signs (arrows) remind the operator of the true flow direction.
Saw tooth appearance on temporal tapping of ECA.
Small regular deflections.
Frequency corresponds to rate of temporal tapping.
Deflections best seen during systole.
Plaque should be evaluated in both sagittal and transverse projections.
Embolism not flow limiting stenosis.
Ulceration…which can serve as nidus for emboli that cause both TIA and stroke.
Studies have shown…..
Plaque can be classified as homogeneous or heterogeneous.
Accurate evaluation of plaque can only be made with grey-scale ultrasound without use of colour or power Doppler.
Calcified plaque. Calcific plaque (arrow) produces a shadow (S), which obscures a portion of the left carotid bulb.
Sonography can accurately determine presence or absence of intraplaque haemorrhage with sensitivity and specificity of……
Heterogeneous plaque in internal carotid artery (ICA). A, Sagittal, and B, transverse, images show
plaque (arrows) virtually completely sonolucent, consistent with heterogeneous plaque (type 1).
C, Sagittal,
and D, transverse, images show focal sonolucent areas within the plaque greater than 50% of plaque volume, corresponding to heterogeneous
plaque (type 2).
Homogeneous plaque. A, Sagittal, and B, transverse, images show homogeneous plaque in left common carotid
artery (type 4). Note the uniform echo texture.
Homogeneous plaque. C, Sagittal, and D, transverse, images show homogeneous plaque in proximal left internal
carotid artery (type 3). Note the focal hypoechoic area within the plaque, estimated at less than 50% of plaque volume.
Although ultrasound reportedly detects intraplaque hemorrhage reliably, in general neither angiography nor sonography has proved highly accurate in identifying ulcerated plaque.
Plaque surface…. Causing an irregular surface or an anechoic area within the plaque that extends to plaque surface without an intervening echo between the vessel lumen and anechoic plaque region.
Color or power doppler demonstrate slow moving eddies of color within an anechoic region within plaque, suggesting ulceration.
Plaque ulceration. A, Color Doppler, and B, power Doppler, longitudinal images show blood flow (arrow) into
hypoechoic ulcerated plaque.
Plaque ulceration and abnormal flow. A, Longitudinal image of the proximal right internal carotid artery
demonstrates heterogeneous plaque with an associated area of reversed low-velocity eddy flow within an ulcer (arrow). B, Pulsed Doppler
waveforms in this ulcer crater demonstrate the extremely damped low-velocity reversed flow, not characteristic of that seen within the
main vessel lumen of the ICA.
Measurement of carotid artery diameter. A, Power Doppler transverse image shows a less than 50%
diameter stenosis (cursors). B, Transverse B-mode flow image of the right carotid bifurcation shows measurement of stenosis (B) in area
of internal carotid artery; A, outer ICA area.
……because
3. Aortic arch proximal to left subclavian artery.
4. The remainder of vertebral arteries enters into the transverse foramen at the C5 or C7 level and, rarely, at the C4 level.
Vertebral artery course. Lateral
diagram of vertebral artery (arrow) shows its course through the
cervical spine transverse foramina (arrowheads) en route to joining
the contralateral vertebral artery to form the basilar artery (B);
C, carotid artery; S, subclavian artery.
4. Through the circle of Willis, the vertebral arteries also provide collateral circulation to other portions of the brain in patients with carotid occlusive disease.
V1 (preforaminal): origin to transverse foramen of C6
V2 (foraminal): from the transverse foramen of C6 to the transverse foramen of C2
V3 (atlantic, extradural or extraspinal): from C2 to the dura
V4 (intradural or intracranial): from the dura to their confluence to form the basilar artery at junction of pons and medulla.
Normal vertebral artery and vein. Longitudinal color Doppler image shows a normal vertebral artery (A) and vein (V) running between the transverse processes of the second to sixth cervical vertebrae (C2-C6), which are identified by their periodic acoustic shadowing (S).
Normal vertebral artery waveform. Normal low-resistance waveform of the vertebral artery with filling of the spectral window.
Vertebral artery flow. A, Subclavian steal causes reversed flow in vertebral artery. Complete vertebral artery flow
reversal results from a right subclavian artery occlusion. Flow in this vertebral artery is toward the transducer
Vertebral artery flow. Slightly aberrant vertebral artery with color flow reversal.
But can be due to changes in head position.
Basilar artery is unaffected unless severe stenosis of vertebral artery supplying the steal exists.
Stages based on hemodynamics.
Incomplete subclavian steal. Flow in early systole is antegrade, flow in peak systole is retrograde, and flow in late systole and diastole (arrow) is again antegrade.
Incomplete subclavian steal and provocative maneuver. A, Presteal left vertebral artery waveform.
Flow decelerates in peak systole but does not reverse. B, After provocative maneuver, there is reversal of flow in peak systole in response
to a decrease in peripheral arterial pressure.
2. …….stenosis less severe than seen in presteal phenomenon.
3. Manoeuvres such as use of bp cuff.