From the 1th April 2018 case
http://www.bailii.org/ew/cases/EWHC/Fam/2018/818.html
“By the time I came to conclude the case, the terrible reality was that almost the entirety of Alfie’s brain had been eroded, leaving only water and Cerebral Spinal Fluid. Even by the end of February, the connective pathways within the white matter of the brain, which facilitate rudimentary sensation – hearing, touch, taste and sight, had been obliterated. They were no longer even identifiable on the MRI scan.”
Clearly, this isn’t the whole truth, or Alfie wouldn’t be Abe to breathe on his own.