To report the safety and efficacy of intra-operative central sulcus (CS) mapping using a 1x4 subdural strip.

The N20/P20 waveform was recorded on scalp and subdural electrodes in 86.7% cases. P25 waveform was recorded on the scalp and subdural electrodes in 100% and 93.3% cases, respectively. Overall, CS was successfully identified in 86.7% cases with the PRT technique. The N20 and P20 peaks were not aligned in any case, and the N20 peak consistently preceded the P20 by ~2.1ms. N20 latency difference between scalp and subdural electrodes was ~1.5ms. The P25 waveform was clearly seen in the electrodes, showing the N20 peak in 93% cases. CS localization took an average of 313.15±306.15 seconds. Tumor location was primarily frontal (53%), with 26% multilobar, 13% parietal, and 7% temporal. Only one patient experienced an intra-op seizure unrelated to CS mapping, and there were no other complications. In 91% cases, no new or worsening neurological deficits were noted up to one month follow-up.

Our study demonstrates a safe, reliable, and efficient method to localize the CS using a 1x4 subdural strip. Our findings are in agreement with the tangential-radial dipole model of median nerve cortical somatosensory evoked potentials.