Thus the angle should be kept between 30-60. 2. As described earlier, it is vital to keep the angle between 30-60 degrees, max at 60 and not beyond. Reduce PRF 2. Increase the color gain 3. Sometimes hyperextension of neck with head turned to contra-lateral side and scanning proximally helps in getting the vertebral artery.
Flow is normal with patient at rest.
In the latter 2, the steal may be intensified and optimally documented by inducing arm hyperemia. A BP cuff is placed around the arm and inflated above systolic pressure. This is seen as spectral broadening. What happens if a carotid bifurcation is high up in the neck, is they anyway to check out the ICA, besides Trans-cranial Doppler. In such patients, far postero-lateral approach may help.