Commentary on: Ultrasound Measurement of Dynamic Changes in Optic Nerve Sheath Diameter During Liposuction Surgery: A...

Xu et al. recently published a prospective clinical trial examining ultrasound-based optic nerve sheath diameter (ONSD) monitoring during liposuction surgery in prone and supine positions, demonstrating that prone position significantly elevates ONSD a validated noninvasive surrogate for intracranial pressure (ICP). While this represents a valuable proofs-of-concept for perioperative ONSD monitoring in cosmetic surgery, several methodological concerns warrant discussion.

We critically appraise four key methodological limitations: (1) exclusive enrollment of female patients without justification, despite established sex differences in ONSD diagnostic accuracy; (2) absence of a predefined clinical action threshold despite reported values remaining below established intervention cutoff; (3) uncontrolled confounding by the dexmedetomidine anesthetic regimen, which has known ICP-lowering properties; and (4) non-randomized group allocation by anatomical region, introducing procedural confounding.

Future studies should incorporate sex-inclusive enrollment, predefined ONSD action thresholds, comparator anesthetic arms, and randomized positioning protocols to validate this promising monitoring approach for broader clinical application.

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