The Collaborative International Dictionary of English v.0.48:

Radioscopy \Ra`di*os"co*py\ (r[=a]`d[i^]*[o^]s"k[-o]*p[y^]), n.
   [Radio- + -scopy.]
   Direct observation of objects opaque to light by means of
   some other form of radiant energy, as x-rays. --
   Ra`di*o*scop"ic (r[=a]`d[i^]*[o^]*sk[o^]p"[i^]k),
   Ra`di*o*scop"ic*al (r[=a]`d[i^]*[o^]*sk[o^]p"[i^]*kal), a.
   [Webster 1913 Suppl.]

WordNet (r) 3.0 (2006):

radioscopy
    n 1: (radiology) examination of the inner structure of opaque
         objects using X rays or other penetrating radiation [syn:
         radioscopy, radiology]