Table 1.

Comparison of internal temperature imaging methods

Method	Absolute or Relative Thermometry	Spatial Resolution	Tissue Penetration	Availability	Cost	Harm to Target Tissue	Implementable using current clinical equipment	Applicable for bedside use
MR	Absolutea and Relativeb	High	High	Widely	High	Heat	Yes	No
Ultrasonography	Relative	Moderate	High	Widely	Moderate	Heat	Yesc and No	Yes
Computed Tomography	Relative	High	High	Widely	High	Ionizing Radiation	Yes	No
Near-Infrared Spectroscopy	Relative	Moderate	Low	Moderately	Moderate	None	Not available	Yes
Microwave Radiometry	Absolute	Moderate	Low	Moderately	Moderate	None	Not available	Yes
Photoacoustic Thermometry	Relative	Moderate	Low	Moderately	Moderate	None	Not available	Yes

^aSpectroscopy, Proton Density, and Temperature-Sensitive Contrast Agents.

^bPRF, T1 relaxation time, T2 relaxation time, and Diffusion.

^cFew clinical ultrasound systems allow implementation of thermography applications.