Source : Webster's Revised Unabridged Dictionary (1913)

Microscopically \Mi`cro*scop"ic*al*ly\, adv.
   By the microscope; with minute inspection; in a microscopic
   manner.

Source : WordNet®

microscopically
     adv 1: by using a microscope; "the blood was examined
            microscopically"
     2: in a microscopic manner; with extreme precision and
        attention to detail; "every manuscript was edited
        microscopically"