How do you decide between using nuclear medicine scanning versus computed tomographic angiography (CTA) for ancillary brain death testing?

I would NEVER use CTA as an ancillary test when determining brain death.

The American Academy of Neurology guidelines specifically classify CT angiography as an unacceptable ancillary test for brain death determination.

The acceptable ancillary tests for adults include digital subtraction angiography (DSA), single-photon emission computed tomography (SPECT), and transcranial Doppler (TCD).

Nuclear medicine perfusion testing (NMPT) remains the preferred test for confirming brain death when ancillary...

Having retired 7-8 years ago, I have a question for the up-to-date Neurologists on this site:

is it still a fact that complete apnea [with at least pCO2 > 60] is a definite sign of brain death?

Paul Schanfield,

Clinical Professor of Neurology, U of MN