Quantitative Photoacoustic Reconstruction of the Optical Properties of Intervertebral Discs Using a Gradient Descent Scheme

The intervertebral discs (IVD) are among the essential organs of human body, ensuring mobility spine. These possess a high proportion water. However, as age, this content decreases, which can potentially lead to various diseases called degenerative disc diseases. This water is therefore an important indicator well-being disc. In paper, we propose photoacoustic imaging means probing and quantitatively recovering its molecular composition, should allow concluding on state. An adjoint-assisted gradient descent scheme implemented recover optical absorption coefficient in disc, from which, if spectroscopic measurements performed, composition be deduced. algorithm was tested synthetic measurements. A realistic numerical phantom built magnetic resonance actual IVD pig. simplified experiment, with single laser source, performed. Results show feasibility using photoacoustics probe IVDs. influences exact approximate formulations studied. impact noise reconstructions also evaluated.