Figure 4

Demonstration of the Craniobot surgical capabilities: (a) A micro-CT scan of an adult male C57BL/6J mouse skull after performing an automated circular craniotomy, drilling an anchor screw pilot hole, and fully excising the skull island. Scale bar, 1 mm. (b) A micro-CT scan of an adult male C57BL/6J mouse skull after milling a 50 µm deep trench for a craniotomy over the majority of the dorsal cortex. Scale bar, 2 mm. (c) Left: A photograph taken from an adult male C57BL/6J mouse skull after a thinning operation using the Craniobot and reinforcing it with clear dental cement and a glass coverslip. Surface milling was performed to a depth of 70 μm in a 2 × 2 mm square. Right: A micro-CT scan of the same mouse. A cross-sectional view of the thinned portion of the intact skull implanted with a glass coverslip. Scale bar, 1 mm. (d) Photographs taken from a female Thy1-GCaMP6f mouse with a chronically implanted circular glass coverslip. Scale bars, 1 mm. (e) Composite image of multiple maximum intensity z-projection images constructed from z-stacks acquired using a 2P microscope from adjacent 365 × 365 µm tiles in the black rectangular area highlighted in d. Scale bars, 100 µm. (f) Left: Average intensity image constructed from 60 s long time series acquired in the tiles highlighted in red and blue squares in e. Scale bar,100 µm. Right: Time series traces of Ca²⁺ activities of individual neurons highlighted by open circles in the average intensity images.