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Updated: Jun 3, 2026

Tumor Hypoxia Assessment: In Vivo 3D Oxygen Imaging Through Electron Paramagnetic Resonance
Published on: February 14, 2025
Measuring oxygen in living tissue: intravascular, interstitial, and "tissue" oxygen measurements
David F Wilson1, Olga S Finikova, Artem Y Lebedev
1Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, PA 19104, USA. wilsondf@mail.med.upenn.edu
Abstract:
Oxygen dependent quenching of phosphorescence has been used to measure the oxygen pressure in both the vasculature of the microcirculation and the interstitial spaces of resting muscle tissue. Oxygen sensitive molecules were either dissolved in the blood (intravascular space) or micro-injected into the interstitial space and the distributions, histograms, of the oxygen pressure were measured. The mean oxygen pressures are higher in the blood than in the interstitial space but the oxygen pressures in the lowest 10% of the two spaces were not significantly different, indicating there is minimal (< 1 mm Hg) oxygen gradient between the two spaces in the capillary bed.
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