The CT, PET, and MRI compatible pressure chamber system allow for non-invasive evaluation of pressurised animas. In this image a full body CT was acquired of a pressurised rat. Using appropriate imaging software, internal organs and physiological processes can be assessed and evaluated.

Due to the limited accessibility to the model animal inside the pressure chamber it is inherently challenging to study biological effects of pressure and decompression, and traditionally, the biological effects of diving have been investigated using different techniques applied after the pressure exposure or decompression (i.e. after the return to the sea level pressure). This strategy, however, may not embrace all relevant aspects of diving physiology.

We have created a novel methodology to study barometric physiology using rodents as model animals; a custom made pressure chamber system compatible with the advanced medical imaging systems (e.g. computed tomography (CT), positron emission tomography (PET), and magnetic resonance imaging (MRI)).

CT, PET and MRI are routinely used to visualise internal morphology and quantify basic physiological parameters non-invasively. While CT visualises particularly hard tissues, MRI can visualise soft tissue anatomy and is capable of measuring certain physiological parameters and metabolites. PET uses synthesised radiolabelled tracers, which mimic endogenous bioactive species, to examine specific metabolic processes.

Combining such imaging systems and pressure chambers has the potential to non-invasively investigate fundamental structural, physiological and metabolic processes in the acute phases of compression and decompression.

Using appropriate tissue representative phantoms for CT, PET and MRI during pressurisation from 101 - 1013 kPa, we have shown that that pressure per se did not affect the acquired signal unpredictably, an important first step for applying this technique in baro-physiological studies.