Single-shot quantitative aberration and scattering length measurements in mouse brain tissues using an extended-source Shack-Hartmann wavefront sensor

TL;DR

This paper introduces an extended-source Shack-Hartmann wavefront sensor (ESSH) that enables accurate, quantitative aberration and scattering length measurements in mouse brain tissues, improving deep fluorescence imaging by enhancing adaptive optics correction.

Contribution

The study presents a novel ESSH method that is more robust to scattering and allows direct measurement of tissue aberrations and scattering length in brain tissues.

Findings

ESSH effectively measures aberrations through thick brain slices.

The method outperforms standard centroid-based approaches in scattering environments.

Tissue scattering length can be quantified using the sensor's geometry.

Abstract

Deep fluorescence imaging in mammalian brain tissues remains challenging due to scattering and optical aberration-induced loss in signal and resolution. Correction of aberrations using adaptive optics (AO) requires their reliable measurement in the tissues. Here, we show that an extended-source Shack-Hartmann wavefront sensor (ESSH) allows quantitative aberration measurements through fixed brain slices with a thickness up to four times their scattering length. We demonstrate in particular that this wavefront measurement method based on image correlation is more robust to scattering compared to the standard centroid-based approach. Finally, we obtain a measurement of the tissue scattering length taking advantage of the geometry of a Shack-Hartmann sensor.