1、Peripheral VascularUltrasoundLiu Liping,Department of Ultrasound,First Affiliated Hospital of Chongqing Medical University,E-MAIL:E-MAIL:QQ:948182963QQ:948182963PART Aneurysm（动脉瘤动脉瘤）Aneurysm（动脉瘤）（动脉瘤）True Aneurysm False Aneurysm Dissective AneurysmAneurysms develop as the structural integrity of the
2、 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 shapesTrue Aneurysm It is abnormal dilations of arteries having at
3、 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-1The artery is dilated locally.The width of dilated segment is 1.5 times wider than that of normal segment.Most aneurysms are fusiform in sha
4、peThe 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.Thrombus can usually be seen in arterial cavity.CDFI shows swirling blood flow pattern.Both transverse and sagit
5、tal images show a fusiform aneurysm with a large amount of thrombus in the arterial wallsDissective 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 sp
6、ace.If there is a full dissection,a false flow lumen is created.Ultrasound findingsThe tearing of intima can be seen;The true and false lumens can be seen;but the entry is difficult to be detectedThrombus can be seen in false lumen;Blood flows may appear in false lumen.But it is less brighter and lo
7、w velocity compared with that in true lumen.Both longitudinal and transverse images show the tearing of intima in an external carotid arteryB-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 oft
8、en 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 findingsA mixed or cystic mass
9、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-f
10、ro waveformclassic to-and-fro waveform Aneurysm（动脉瘤）（动脉瘤）Aneurysm（动脉瘤）（动脉瘤）PART Arteriosclerotic Occlusive Disease（动脉硬化（动脉硬化性闭塞性性闭塞性疾病）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 hyper
11、tension diabetes elevated cholesterol tobacco smoking a family history of atherosclerosisInjury 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 occlusionPlaque Characteriz
12、ationPlaque 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 plaqueHypoechoic plaqueCalcifi
13、ed plaqueHyperechoic plaquea crater suggesting an ulcerheterogeneous-intraplaque hemorrhageblood 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 CD
14、FI:the narrow multicoloured jet blood flow signals through stenosis PW:high speed flow with wide frequency bandPART Deep Vein Thrombosis深静脉血栓深静脉血栓(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,pregnanc
15、y 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 swellin
16、g of the thigh.Signs and Symptoms1.Acute thrombus(within 2 weeks)2.Sub-acute thrombus(more than two weeks)3.Chronic thrombus(several months to years)Ultrasound FindingsThe distinction between acute and chronic DVT is difficult on all imaging modalities The vein is enlarged obviously;compressing acti
17、on can not make the cavity shrunken;The internal echoes of cavity are echo-free or hypoechoic;No blood flows with complete thrombosis.1.Acute Thrombus The deep veins of the lower extremity are filled and distended by acute hypoechoic thrombusThe acute hypoechoic thrombus filling and distending deep
18、vein does not compress The size of cavity may become normal;The internal echoes of DVT increase;The re-opening may occur and CDFI can show blood flow in different shapes in the cavity.2.Sub-acute thrombus A-a thrombus around jugular vein catheter.B-CDFI shows an color void or defect.They appear more
19、 echogenic than acute clots;The wall is thickened,irregular,echogenic,the vein is incompletely compressible;CDFI show blood flows in cavity when complete or partial re-opening occurs.3.Chronic thrombus A-an acute thrombus distending the vein.B-partial recanalization with chronic DVT remaining after
20、2 months.PW shows straight wave of lower limb veins with no response to Valsalva or respiration.It indicates a more proximal obstruction.Venous Insufficiency Veins contain valves to prevent the reflux of blood to the extremities.Venous insufficiency occurs when the lower extremity venous valves are
21、destroyed or become incompetent.Chronic venous insufficiency is caused by valvular damage following DVT in about 40%of individuals.However,the other 60%of patients with venous insufficiency have incompetent valves,unrelated to DVT.Pathophysiology Clinically,venous insufficiency leads to leg swelling
22、,chronic skin changes such as eczema,pigmentation,woody induration and nonhealing venous stasis ulcers finally.Signs and Symptoms Superficial venous insufficiency leads to distended subcutaneous varicosities.1.Subcutaneous varicosities.2.CDFI:retrograde flow during a Valsalva action or following dis
23、tal squeeze release.3.PW:reflux wave(reflux duration1 s).4.The degree of reflux is assessed by reflux duration and the velocity of reflux.Ultrasound FindingsA-Subcutaneous varicosities of right leg.B-The B-mode image showed tortuous dilated varicose veins.Subcutaneous VaricositiesA：flow in the SSV a
24、nd POV is antegrade during distal squeeze(blue).B：significant retrograde flow(red)due to saphenopopliteal junction incompetence following squeeze release A-Retrograde blue flow indicates partial venous insufficiency.B-PW showed low-velocity reflux following squeeze release.450ms2sA-Augmentation following calf compression.There is a short duration of normal retrograde flow as the venous valves close.B-Severe venous reflux during a whole Valsalva action(ruflux duration 2s.1/16/2023
