Abstract
BACKGROUND: In vivo cortex optical imaging methods for visualization of both structural and functional architecture with high spatial-temporal resolution have shown tremendous advantages in the studies on neurons, glia and microvasculature. To overcome the strong scattering of skull above the cortex, several chronic cranial windows were proposed through craniotomy, but there are some problems. Here, an innovative skull optical clearing solution (SOCS) has been invented to make the skull transparent within 25 min, but SOCS-induced optical clearing efficacy of skull is to be evaluated. METHODS: Based on the measurements of divergence of beam spot, collimated transmittance of skull, the efficiency of skull optical clearing has been further evaluated quantitatively by comparing with the Monte Carlo simulation. RESULTS: The results show that the light beam bandwidth is 5.2±0.3 mm through the initial skull, and reduces to 2.0±0.2 mm trough the treated skull with SOCS; and the calculated scattering coefficient almost decreases to one third after the treatment. CONCLUSIONS: The quantitative evaluation of SOCS-induced optical clearing efficacy of skull provides an important reference for performing transcranial cortical optical imaging or operation based on skull optical clearing technique.