Multispectral optoacoustic tomography of the human intestine - temporal precision and the influence of postprandial gastrointestinal blood flow.

Multispectral optoacoustic tomography (MSOT) holds great promise as a non-invasive diagnostic tool for inflammatory bowel diseases. Yet, reliability and the impact of physiological processes during fasting and after food intake on optoacoustic signals have not been studied. In the present investigator initiated trial (NCT05160077) the intestines of ten healthy subjects were examined by MSOT at eight timepoints on two days, one fasting and one after food intake. While within-timepoint and within-day reproducibility were good for single wavelength 800 nm and total hemoglobin (ICC 0.722-0.956), between-day reproducibility was inferior (ICC -0.137 to 0.438). However, temporal variability was smaller than variation between individuals (coefficients of variation 8.9%-33.7% vs. 17.0%-48.5%). After food intake and consecutive increased intestinal circulation, indicated by reduced resistance index of simultaneous Doppler ultrasound, optoacoustic signals did not alter significantly. In summary, this study demonstrates high reliability and temporal stability of MSOT for imaging the human intestine during fasting and after food intake.
Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Markus F Neurath, Maximilian J Waldner, Ferdinand Knieling reports financial support was provided by European Union. Adrian P Regensburger reports financial support was provided by Friedrich Alexander University Erlangen Nuremberg Faculty of Medicine. Adrian P Regensburger, Ferdinand Knieling, Maximilian J Waldner has patent issued to iThera Medical GmbH, Munich, Germany. Ferdinand Knieling is a section editor of the Journal Photoacoustics, however no involved in the peer review process of this manuscript.
(© 2023 The Authors.)