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Brain-Imaging-Center / TMS-fMRI

Technical developments for simultaneous TMS-fMRI
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Develop QA routine for TMS coil #8

Open BenInglis opened 9 years ago

BenInglis commented 9 years ago

We need a way to assess wear and tear, e.g. to check the temperature rise for a particular protocol.

DobyRahnev commented 9 years ago

I've created a google sheets as a simple log. We should think about acoustic or other tests too.

BenInglis commented 8 years ago

Pilot QA routine tested for a TMS pulse set to occur just after the three Nyquist ghost correction echoes and before the start of k-space readout. This corresponds to 250th increment of 0.1 ms on top of the timing established under issue #5.

The acquisition protocol consists of 50 TR periods with no TMS pulse, during which the phantom is withdrawn from the birdcage coil, the magnet room lights switched off and the door closed. TMS pulses occur one per TR for volumes 51-150. Then a further 100 volumes are acquired with no TMS pulses.

ROI plots in Mean Curve clearly show the effect of the TMS pulses in the target slice (red box) but also show that later slices (eg yellow box) show higher numbers of birdies than either a slice acquired before TMS in the current TR period (turquoise box) or very late in the TR period (green box). Eliminating the TMS pulses during the final 100 volumes returns the RF noise to baseline.

tms_rfi_qa

Starting/ending temperatures weren't recorded but were approx. 24 C. The number of remaining TMS pulses as given on the MagPro box after the completion of the QA scan was 24,412.