Detection of increased intracranial pressure in trans-oral robotic thyroidectomy using optic nerve sheath diameter measurement

Background: During transoral robot-assisted thyroidectomy, there is a risk of increasing intracranial pressure because the site of CO₂ insufflation is narrow and close to the brain.

Methods: We analyzed the pre- to post-CO₂ neck insufflation change in the optic nerve sheath diameter during transoral robot-assisted thyroidectomy. Changes in vital-signs, airway pressure, and arterial carbon dioxide pressure were analyzed along with postoperative complications.

Results: Among the 30 participants, the post-CO₂ inflation mean optic nerve sheath diameter (5.64 ± 0.54 mm) was higher than the pre-induction diameter (4.81 ± 0.37 mm) with a mean difference of 0.83 (95% CI, 0.69-0.97; p < 0.001), but returned to baseline after CO₂ deflation in most cases. One participant had sustained increased optic nerve sheath diameter (6.35 mm) associated with severe new-onset postoperative headache.

Conclusion: Transient elevation in the intracranial pressure during low-pressure CO₂ neck insufflation in the transoral robot-assisted thyroidectomy did not appear to adversely affect patients.