Page 127 - Libro vascular I

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PERIPHERAL VASCULAR ULTRASOUND
from an aneurysm. In this situation it is not unusual for the patient to have a palpable popliteal pulse.
Microembolization into the foot is often called ‘trash foot’. Localized tissue necrosis can occur and the outcome is sometimes poor when a large area of tissue is affected.
PRACTICAL CONSIDERATIONS FOR
LOWER EXTREMITY DUPLEX SCANNING
The objective of the examination is to locate and grade the severity of arterial disease in the lower
limb arterial system. The time allocated for the exam- ination depends on the number of segments that need assessing. The femoropopliteal segment can normally be examined in both legs in half an hour. However, a bilateral aortoiliac to ankle scan may take up to an hour and a half, depending on experi- ence. There is usually no special preparation required before a lower limb duplex scan. Nevertheless, some vascular units request patients to fast overnight prior to an examination of the aortoiliac arteries to improve imaging of this region. In our experience this is of little help, especially if patients require scans
CFA
V
CFA
12 3
4 5
6
Figure 9.6 The anatomy of the right femoral artery and vein at the groin, with corresponding transverse B-mode images at four different levels. Vessels shown on the diagram are: 1 common femoral artery, 2 common femoral vein,
3 saphenofemoral junction, 4 superficial femoral artery, 5 profunda femoris artery, 6 superficial femoral vein,
7 profunda vein. Vessels demonstrated on the images are the common femoral vein (V), common femoral artery (CFA), saphenofemoral junction (SFJ), superficial femoral artery (SFA), profunda femoris artery (PA), superficial femoral vein (SFV) and profunda vein (PV). Note that the femoral artery bifurcation is sometimes found above the level of the saphenofemoral junction. In addition, the superficial femoral artery tends to roll on top of the superficial femoral vein, as shown in the B-mode image.
V
SFJ
SFA
7
SFA SFV
PV
PA
V
PA