Peripheral Vascular Ultrasound,Liu Liping, Department of Ultrasound, First Affiliated Hospital of Chongqing Medical University, E-MAIL: liuliu417325163.com QQ: 948182963,PART Aneurysm （动脉瘤）,Aneurysm（动脉瘤）,True Aneurysm False Aneurysm Dissective Aneurysm,Aneurysms develop as the structural integrity of the arterial wall weakens.,A: fusiform; B: tortuous elongated; C: saccular; D: infrarenal; E: suprarenal; F and G: dissecting; I: False aneurysm .,Aneurysms develop as the structural integrity of the arterial wall weakens.,Aneurysms are very variable in shapes,True Aneurysm,It is abnormal dilations of arteries having at least a 50% increase in diameter compared to the normal diameter. It is often caused by arteriosclerosis. It is the common type in aneurysms.,Ultrasound findings-1,The artery is dilated locally. The width of dilated segment is 1.5 times wider than that of normal segment. Most aneurysms are fusiform in shape The three layers of arterial wall can be seen.,The abdominal aorta is dilated locally. It measures 51mm in the anteroposterior dimension. The distal normal artery measures 20mm in diameter.,A,B,C,Thrombus can usually be seen in arterial cavity. CDFI shows swirling blood flow pattern.,Both transverse and sagittal images show a fusiform aneurysm with a large amount of thrombus in the arterial walls,Dissective Aneurysm,Dissecting ananeurysm can occur due to a tear in the intima and blood can enter the subintimal space. If the aorta partially dissects, large amounts of thrombus may be seen in the subintimal space. If there is a full dissection, a false flow lumen is created.,Ultrasound findings,The tearing of intima can be seen; The true and false lumens can be seen; but the entry is difficult to be detected Thrombus can be seen in false lumen; Blood flows may appear in false lumen. But it is less brighter and low velocity compared with that in true lumen.,Both longitudinal and transverse images show the tearing of intima in an external carotid artery,B-mode image of a dissecting aortic aneurysm. the true and false lumens are seen. Color flow imaging demonstrates flow in the false lumen.,False Aneurysm,It is often caused by trauma, angiography or surgery after artery puncture. Blood continues to flow backward and forward through the puncture site into a false flow cavity outside the artery. The wall of aneurysm is made up of hematoma and surrounding compressed tissue.,Ultrasound findings,A mixed or cystic mass can be seen by the side of artery; Sometimes a narrow route from artery to the mass can be imaged; Thrombus can be seen within the mass; CDFI: the blood flow within the mass is eddied flow.,Systolic and diastolic images of false aneurysm: A: swirling motion of blood; B: a small channel. C: the classic to-and-fro waveform,A,B,C,classic to-and-fro waveform,Aneurysm（动脉瘤）,Aneurysm（动脉瘤）,PART Arteriosclerotic Occlusive Disease（动脉硬化性闭塞性疾病） (ASO),It is due to arteriosclerosis. It often occurs at large-medium sized arteries in the elderly. Several risk factors are associated with ASO:,increasing age hypertension diabetes elevated cholesterol tobacco smoking a family history of atherosclerosis,Injury to the vascular endothelium progressive deposition of lipids, proliferation of smooth muscle cells, and migration of fibrocytes plaque forming and growing vascular stenosis (狭窄)or occlusion,Plaque Characterization,Plaque is usually described by surface feature, density, and texture. Surface features are smooth, irregular, and ulcerated. Hypoechoic, isoechoic, and hyperechoic are the terms used to describe plaque density. Plaque texture is either homogeneous or heterogeneous.,Anechoic plaque,Hypoechoic plaque,Calcified plaque,Hyperechoic plaque,A: a crater suggesting an ulcer B: heterogeneous - intraplaque hemorrhage,A,B,blood flows into ulcerated plaques ( hyperechoic and hypoechoic heterogeneous ),CDFI: narrow bloodstream means arterial stenosis PW: high speed wave and wide frequency band,2D: the plaque makes the artery stenosis CDFI: the narrow multicoloured jet blood flow signals through stenosis PW: high speed flow with wide frequency band,PART Deep Vein Thrombosis 深静脉血栓 (DVT),DVT is a common disorder that can lead to fatal pulmonary embolism. DVT usually affects the lower limb veins, especially due to trauma, surgery, pregnancy or malignancy.,Epidemiology and Pathology,Typical symptoms include pain, tenderness, heat and swelling. But these signs are nonspecific and can be caused by several local or systemic conditions. The superficial veins may be dilated. If the DVT involves the proximal veins, there may be significant swelling of the thigh.,Signs and Symptoms,Acute thrombus (within 2 weeks ) Sub-acute thrombus ( more than two weeks ) Chronic thrombus ( several months to years ),Ultrasound Findings,The distinction between acute and chronic DVT is difficult on all imaging modalities,The vein is enlarged obviously; compressing action can not make