The fMRI scans will be performed on

The fMRI scans will be performed on the first 100 eligible patients within 1 month before and 6 weeks after surgery ina 3-T scanner with an eight-channel head coil. Anatomical scan sequences are high-resolution T1-weighted fastspoiled gradient-echo oblique axial acquisitions (256 ×256 matrix, 256-mm field-of-view [FOV], 11-degree flipangle, 136 1-mm-thick slices, TR/TE, 6.93/3.0 ms), and T2 fluid-attenuated inversion recovery oblique axial acquisitions (128 × 128 matrix, 256-mm FOV, 90-degree flip angle, 68 2-mm-thick slices, TR/TE, 2250/11 000 ms, inversion time 2250 ms).The two resting-state fMRI sequences are sensitivity-encoding, spiral-in, oblique, axial, sliceinterleaved acquisitions (64 × 64 matrix, 256-mm FOV,60-degree flip angle, 34 4-mm-thick slices, TR/TE 3000/30ms, sensitivity-encoding factor 2). The first 18 seconds ofeach resting-state fMRI sequence is discarded to correct for initial MR signal fluctuation. Data from the next 124 time points (6.2 min) is retained for functional connectivity analysis. To minimize head motion during scans, we use a firm head rest and instruct participants to remain still.The fMRI scans focus primarily on predefined regions of interest in the DMN and salience network. Based on our pilot data, we expect increases in CSF MCP-1 and monocyte-tolymphocyte ratio from before to 24 hours after surgery to predict altered inter-network resting-state connectivity between the anterior to posterior cingulate from before to 6 weeks after surgery. Anatomical and perfusion MRI sequences allow us to account for effects of potential fMRI data confounders and to facilitate additional analyses.