Account for scalp-generated photoacoustic signals and skull reflections that corrupt cortical signals

Develop a transcranial photoacoustic computed tomography reconstruction framework that models and accounts for photoacoustic signals generated outside the skull (including hair follicles and melanin in the scalp), their reflections from the skull, and the resulting deterministic background to prevent corruption of intracranial cortical signals.

Background

In noninvasive configurations, the authors observe a strong deterministic background arising from the skull and note that in vivo there is similar deterministic background from scalp-generated signals reflecting off the skull. These reflections can dominate and corrupt weaker intracranial signals.

They explicitly identify accounting for these reflections as the next major challenge for transcranial PACT and state that this will be the focus of future work, underscoring its importance for robust cortical imaging.