**4.8 Flow registration**

It represents the system's ability to give a colour signal exactly superimposed on the morphology of the pseudo-vessel. The check consists of carrying out a scan of a vessel using the Colour Doppler mode and verifying that the colour information on the flow is contained within the vessel, does not overflow but does not leave areas with an absence of colours, especially near the walls. It is a first-level test. Value obtained is very spread.

Particular attention must be taken to the overlap colour-B-mode.

#### **4.9 Temporal resolution**

It is related to the colour frame rate of the image. A dynamic event is simulated: speeds change rapidly and acceptable reproduction of dynamics in the image is verified. It's a first-level test.

#### **4.10 Motion discrimination**

It represents the system's ability to discriminate between the movement of liquid and solid masses. It is influenced by the choice of wall filter.

It is checked by simulating a known flow in a pseudo-vessel with very elastic and extensible walls and evaluating the signal of the walls, which appear displayed and which must not be in colour. It's a second-level test.

Referring to the frequency of evaluations, there are no indications whatsoever from international bodies or centres with particular experience.
