Examines surgical instruments (6)
I believe the answer is:
probes
I believe this clue is a double definition.
'examines' is the first definition.
('probe' can be a synonym of 'examine')
'surgical instruments' is the second definition.
(probe is a kind of surgical instrument)
(Other definitions for probes that I've seen before include "Examines as dentist does decaying tooth" , "Conducts penetrating investigation" , "Investigates closely" , "Investigates as dentist does tooth" , "Questions or examines thoroughly" .)