下肢血管-英文.ppt

Dissecting aneurysms 2. Color flow images Ture aneurysm False aneurysms Dissecting aneurysms cause atherosclerosis injury, infection atherosclerosis, marfan syndrome B-mode images the artery enlarge arteria cystic mass a ture lumen and a false lumen wall of the aneurysm arterial wall surrounding tissue color flow images disturbance ‘yin-yang’ sign color flow in ture lumen and false lumen in different directions Antidiastole Thromboangiitis obliterans, TO 1. Clinical: Often involving the small and medium-sized artery and accompanying vein， segmental distribution， more common in males ，smokers ，20~40 year old. Thromboangiitis obliterans, TO B-mode images: Rough intimal, vascular wall uneven thickening, the inside diameter of the artery decreased, often below the popliteal artery. Thromboangiitis obliterans, TO Color flow images ：Flow signals changed to be fine, defect or dot-like; if complete occlusion, no flow signal in the artery. Thromboangiitis obliterans, TO 4. Spectral Doppler: Variation Mild lesions: a triphasic flow pattern with a clear spectral window; most cases: the wave form may be monophonic； complete occlusion: no wave form can be found. male ,56Y thromboangiitis obliterans in the left anterior tibial artery male ,56Y thromboangiitis obliterans in the left anterior tibial artery male ,56Y thromboangiitis obliterans in the left anterior tibial artery Atherosclerosis The earliest ultrasound sign is thickening of the intima and media (1.0mm) , in the bifurcation (1.2mm) Atherosclerosis Atheroma：the intima and media (1.5mm) Multilevel disease and bilateral involvement are common. L-CFA R-CFA Atherosclerosis 2. Color flow images： Flow signals change to be fine or defect. Arterial stenoses will be demonstrated as areas of color flow disturbance or aliasing. An occlusion is demonstrated by a total absence of color flow in the vessel. Atherosclerosis 3. Spectral Doppler： If the artery is no significant stenosis, spectral doppler is