Overview of Technical Application

In all cases, a linear, high-frequency probe (as shown here) should be selected. The machine should be set to an appropriate depth, where the vessel fills at least half of the screen. This will maximise resolution and aid in needle tip visualisation.

Time Gain Compensation (TGC) should be flat. In all cases avoid zoom or the skin surface will not be seen.

For a junior trainee this may be the first use of ultrasound in order to carry out an intervention. There are new skill sets to learn. When introducing a needle into tissue, with the hope of seeing it on the screen, two key technical issues are:

• Parallelism
• Angle of approach