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.
Journal article
Tomography
06/2019
5
274 - 281
MR-CT-PET-SPECT compatibility, carbon fiber, heater, multimodal imaging