contacting a tip of {HEAD ~ a biopsy instrument} to {TAIL ~ the membrane} so that the tip is displayed in the ultrasound image 
contacting a tip of { HEAD ~ a biopsy instrument } to { TAIL ~ the membrane } so that the tip is displayed in the ultrasound image
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH