Ultrasonographic Evaluation of Intraoperative Optic Nerve Sheath Diameter Changes as a Surrogate for Intracranial Pressure Monitoring during Laparoscopic Surgery

Abstract

This study investigates the feasibility of using ultrasonographically measured changes in optic nerve sheath diameter (ONSD) as a surrogate for monitoring intracranial pressure (ICP) during laparoscopic surgery. Elevated ICP is a critical condition that can lead to significant morbidity; thus, effective monitoring is essential.

In this prospective observational study, we enrolled 80 patients undergoing elective laparoscopic surgery. Preoperative baseline ONSD measurements were obtained, followed by intraoperative measurements at specified intervals: after induction, during surgery, and before extubation. Changes in ONSD were correlated with intraoperative hemodynamic parameters and postoperative neurological outcomes.

Results demonstrated a significant increase in ONSD from baseline to intraoperative measurements (p < 0.01). Furthermore, changes in ONSD correlated with intraoperative fluctuations in mean arterial pressure and heart rate. Postoperatively, patients with greater ONSD changes were more likely to exhibit neurological complications.

In conclusion, ultrasonographic measurement of ONSD is a promising non-invasive method for monitoring changes in ICP during laparoscopic procedures, potentially aiding in the prevention and management of intracranial hypertension.
Keywords: optic nerve sheath diameter, intracranial pressure, laparoscopic surgery, ultrasonography, neuromonitoring.