A Carbon-Fiber Sheet Resistor for MR-, CT-, SPECT-, and PET-Compatible Temperature Maintenance in Small Animals

Tomography. 2019 Jun;5(2):274-281. doi: 10.18383/j.tom.2019.00008.


A magnetic resonance (MR)-, computed tomography (CT)-, single-photon emission computed tomography (SPECT)-, and positron emission tomography (PET)-compatible carbon-fiber sheet resistor for temperature maintenance in small animals where space limitations prevent the use of circulating fluids was developed. A 250 Ω carbon-fiber sheet resistor was mounted to the underside of an imaging cradle. Alternating current, operating at 99 kHz, and with a power of 1-2 W, was applied to the resistor providing a cradle base temperature of ∼37°C. Temperature control was implemented with a proportional-integral-derivative controller, and temperature maintenance was demonstrated in 4 mice positioned in both MR and PET/SPECT/CT scanners. MR and CT compatibility were also shown, and multimodal MR-CT-PET-SPECT imaging of the mouse abdomen was performed in vivo. Core temperature was maintained at 35.5°C ± 0.2°C. No line-shape, frequency, or image distortions attributable to the current flow through the heater were observed on MR. Upon CT imaging, no heater-related artifacts were observed when carbon-fiber was used. Multimodal imaging was performed and images could be easily coregistered, displayed, analyzed, and presented. Carbon fiber sheet resistors powered with high-frequency alternating current allow homeothermic maintenance that is compatible with multimodal imaging. The heater is small, and it is easy to produce and integrate into multimodal imaging cradles.

Keywords: MR-CT-PET-SPECT compatibility; carbon fiber; heater; multimodal imaging.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Body Temperature / physiology*
  • Carbon Fiber*
  • Female
  • Heating / instrumentation*
  • Image Processing, Computer-Assisted / methods*
  • Magnetic Resonance Imaging / methods*
  • Mice
  • Mice, Inbred CBA
  • Models, Animal
  • Multimodal Imaging / methods
  • Positron-Emission Tomography / methods
  • Tomography, Emission-Computed, Single-Photon / methods
  • Tomography, X-Ray Computed / methods*


  • Carbon Fiber