pearls for diagnosis

1-• Be sure the veins fully compress.
2-Be sure to apply pressure evenly along the transducer face (perpendicular to skin surface). 3-Avoid pressing at an angle, as this may result in uneven compression and a false positive finding. 3-In patients who are obese, decreasing the transducer frequency to 3.5-5 MHz increases the depth of penetration and can assist the examiner. Overall image quality, however, is reduced.
4- If no vein is visible at the appropriate anatomic sight, the transducer may already be compressing the vein. Reduce the amount of pressure being applied and reexamine the area of interest.
5-Care must be taken to not over-interpret vessel echogenicity as clot. Both normal blood flow and vessel artifact can appear hyperechoic. Cysts, especially Baker cysts, are commonly encountered in the popliteal region.
6-These can be readily distinguished by their confluence with the joint space and their lack of flow on color flow Doppler ultrasonography.
7-Lymph nodes are particularly common in the femoral region and can be identified by their superficial location, their characteristic appearance (hyperechoic center with hypoechoic rim), and their high vascularity on color flow Doppler ultrasonography
8- Duplicate popliteal and femoral veins are not uncommon. Special attention must be paid to rule out a DVT in patients with a duplicate vessel because the potential decrease in flow velocity may increase the risk for clot development.
9- Utilizing the dual-image picture or split-screen option before and after compression may make comparison easier. In addition, the split-screen option may be useful in hospitals that use still images for documentation. If the examination site is wounded, the ultrasound transducer may be covered with a sterile probe cover with gel applied to both the inside and the outside of the cover.If an adequate examination cannot be obtained secondary to patient body habitus, patient compliance, or skill limitation, the patient requires a formal ultrasonographic study. In addition, if the study results are indeterminate, then a formal ultrasonographic study should be obtained.


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