Title: Synchronization of kinetic and kinematic hand tasks with electrocorticography and cortical stimulation during awake craniotomies
Intraoperative direct cortical stimulation (DCS) is standard of care to verify functional-anatomical relationships of critical brain areas during awake craniotomies. Quantizing general measures of kinetic and kinematic motor responses would minimize subjective fluctuation and improve mapping confidence. Furthermore, there is enormous opportunity for scientific inquiry into motor neurophysiology during these cases if the data is carefully collected and synchronized.
Methods for quantizing motor responses during awake craniotomies must aim to minimize disruption to operating room (OR) staff and the procedure. The methodology defined here aims to allow for the synchronized assessment of whole hand kinematics, kinetics, DCS, electrocorticography (ECOG), surgical video, and task video.
We use a high-resolution force mat, a 23-degree-of-freedom (DoF) data glove, a standard clinical Nihon Kohden, and a custom synchronization platform to collect our data. Synchronization of the devices in the intraoperative set-up relies on a shared button-gated TTL voltage signal where the data stream for a task is marked or initiated a button press. MATLAB and Python are used for post-processing of the data streams.
Each recording on-set was assessed for lag from a button-press initiation to data being recorded. The 95% lag confidence interval for whole hand kinematics, kinetics, DCS, electrocorticography (ECOG), surgical video, and task video streams were 95.3-95.7 ms, 0.0-5.0 ms, 0.0-0.1ms, 0.0-34.0, and 0.0-34.0 ms, respectively.
This methodology allows for minimal impact on the many other tasks being performed in the operating room. The set-up in the operating room can occur prior to the surgery and quickly. Using cable management techniques, normal operating room activity can be unhindered with the operator of the synchronization circuit at a distance. The data produced was reliably synchronized and can provide important insights into motor neurophysiology.