We all have clear that nowadays skin ultrasound without Doppler is like losing 50% of possible information on a skin lesion (inflammatory or tumoral)
Skin ultrasound doppler is usually difficult to perform due to three reasons:
- Superficiality of vessels= compressibility=no flow
- Small caliber of vessels
- Lack of knowledge on Doppler principles.
In this post I want to offer some tips to improve your Doppler scans in skin lesions. However, improving Doppler means continuously learning Doppler by performing Doppler scans.
1. Use a large amount of gel and avoid using pads that press the vessels.
2. Get first a good image of the structure under study in B-mode.
3. Select Color or Power Doppler depending on flow direction information necessity.
4. Adapt the size of the visualization window to the vessel.
5. Set PRF starting from 750 KHz
6. Adjust Doppler time-gain to the point immediately preceding the flare artifact.
7. Acquire images in several moments as flow changes with time. (see post on New technologies for flow measurement)
8. In skin lesions insonation angle does not influence usually presence of flow as vessels are so small and arborizing that flow is usually present if present.
However keep angle for comparisons.
9. If performing Pulsed Doppler (avoid it when doing scans that involve long exposures because it produces heat) select and position gate on the center of the vessel.
10. Perform the necessary measurements on the frozen spectrum.
I hope you have found these pearls and tricks of interest for your clinical practice
Not performing skin ultrasound doppler is a barrier mainly dependent on laziness, ignorance and scenic fear. Not performing skin ultrasound doppler is missing amazing phenomena happening in front of you without noticing.