An effective amount of a photosensitive agent for {TAIL ~ PDT} is administered to {HEAD ~ a patient} 
An effective amount of a photosensitive agent for { TAIL ~ PDT } is administered to { HEAD ~ a patient }
OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD