The acquired motion NMR data is processed on line to produce a signal indicative of {HEAD ~ the displacement} of the abdominal wall from {TAIL ~ a reference position} 
from
The acquired motion NMR data is processed on line to produce a signal indicative of { HEAD ~ the displacement } of the abdominal wall from { TAIL ~ a reference position }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL