3TQA

3T QA procedure

The QA procedure contains several steps. Make sure there is no patch activated while doing them.

1) PIQT

2) Spurious test

3) IQT

4) EPI stability

5) Helium level

PIQT

This scan evaluates internal parameters of the scanner, including the stability of the gradient coils. This is done by scanning a phantom from which the specs are known.

Duration: 20 minutes

Preparation:

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  Photo 1
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  Photo 2
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  Photo 3
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  Photo 4
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  Photo 5

• Get the NVC head coil and 200 mm head phantom and phantom holder.
• Check whether the phantom contains air (bubbles). If so, they shouldn't be larger than about a centimes in width.
• Place the base of the coil on the patient table and remove the cushion.
• Position the phantom in the transverse orientation. The 'T' Marker on the phantom should point to the front side of the magnet as indicated by the red circle on Photo 3.Check whether the phantom is inserted correctly; it should be positioned as far back in the coil as possible (i.e. towards the bore) and it shouldn't be able to rotate sideways.
• Place the top part on the coil.
• Position the coil using the light visor; the beam must be on the horizontal line.
• Use Travel to scan plane to position the coil in the magnet center.

How to run:

• On the scan computer: System --> SPT --> Batch Files --> PIQT
• Right-click --> Run batch

Output:

After the PIQT scan finishes, a window pops up, ignore this window and then:

• Image view --> right click on PIQT --> generate reports.
• This generates an HTML-file with values for the tested parameters. If any values are marked in red, it means that the scanner is out-of-spec.
• Print the HTML-file as PDF and save this into scdropbox --> 3T_QA --> create a new folder with the current date (e.g. '20220803') --> 'currentdate_PIQT.pdf'

What if the PIQT indicates problems:

There are a couple of things that you should check before reporting PIQT issues to Philips.

• Check whether the head coil is closed correctly and check whether the cable from the coil into the table is inserted correctly.
• Check whether the phantom is inserted correctly; it should be perfectly in the middle (no room to wiggle).
• Check if there is too much air (bubbles) in the PIQT phantom (larger than 1 cm).

After checking (and fixing) the above points, redo the PIQT scan and report to Philips if there are still signs of scanner issues (red values).