Source : Webster's Revised Unabridged Dictionary (1913)

Thermography \Ther*mog"ra*phy\, n. [Thermo- + -graphy.]
   Any process of writing involving the use of heat.

Source : WordNet®

thermography
     n : diagnostic technique using a thermograph to record the heat
         produced by different parts of the body; used to study
         blood flow and to detect tumors