In Vivo Deep Tissue Imaging via Iterative Multiphoton Adaptive Compensation Technique

Multiphoton microscopy has been widely adopted in biological studies for its advantages in deep tissue imaging at subcellular resolutions. However, aberration and scattering in the sample often lead to a distorted laser focus with reduced focus intensity, limiting the achievable resolution and penetration depth. Adaptive optics has been adopted in microscopy to correct wavefront distortions and recover the diffraction-limited focus. Here, we review the Iterative MultiPhoton Adaptive Compensation Technique (IMPACT) that can perform in vivo high-speed wavefront measurement and compensation at large depth. We describe the working principle of IMPACT, demonstrate its applications for in vivo deep tissue imaging, and discuss its advantages and aspects to be improved.