Photoacoustic imaging is an emerging hybrid technique that can detect deep optical absorption contrast with unprecedented spatial resolution in optical imaging. However, the performance of photoacoustic imaging in brain has been hindered by the presence of the skull. The skull will attenuate the light due to its turbidity. It will also diminish the stimulated ultrasound due to the high attenuation coefficient of the skull and mismatch of the acoustic impendence between the skull and soft tissues. Therefore, reducing the impact of the skull in photoacoustic imaging is highly desirable

In this manuscript, a newly developed skull optical clearing solution (SOCS) was introduced in the AR-PAM for imaging cortical microvasculature with the skull intact. we demonstrated that a newly developed skull optical. We demonstrated that clearing solution (SOCS) could enhance not only the transmittance of light, but also that of ultrasound in the skull in vitro. Thus the photoacoustic signal was effectively elevated, and the relative strength of the artifacts induced by the skull could be suppressed.Furthermore in vivo studies demonstrated that SOCS could drastically enhance the performance of photoacoustic microscopy forcerebral microvasculature imaging. This manuscript was published in IEEE Transactions on Medical Imaging (Vol.35, No.8, pp.1903-1906, 2016).

This work was supported in part by National Major Scientific Research Program of China (2011CB910401), in part by Science Fund for Creative Research Group of China (61121004), National Natural Science Foundation of China (81201067, 81171376, 91232710, 812111313) and in part by Director Fund of WNLO.

The image shows the in vivo imaging results of a mouse cerebral vasculature obtained by a Gaussian beam PAM and a Bessel beam PAM, more vessels can be revealed by the latter one.