Intraoperative optic nerve sheath diameter changes in vNOTES versus total laparoscopic hysterectomy: a prospective...

Area of Science:

• Minimally invasive gynecologic surgery
• Neuroanesthesia and critical care
• Surgical innovation

Background:

• Laparoscopic hysterectomy with pneumoperitoneum and steep Trendelenburg positioning may elevate intracranial pressure.
• Optic nerve sheath diameter (ONSD) measured via ultrasonography is a noninvasive intracranial pressure indicator.
• Vaginal natural orifice transluminal endoscopic surgery (vNOTES) offers a less invasive alternative to total laparoscopic hysterectomy (TLH), potentially reducing intra-abdominal pressure and Trendelenburg steepness.

Purpose of the Study:

• To compare the intraoperative effects of vNOTES and TLH on ONSD.
• To evaluate whether vNOTES is associated with less ONSD increase compared to TLH.
• To assess postoperative outcomes including nausea and vomiting.

Main Methods:

• A prospective randomized trial involving 66 patients undergoing elective hysterectomy.
• Patients were randomized to either vNOTES (n=33) or TLH (n=33).
• Bilateral ONSD measurements were taken using transorbital ultrasonography at set intraoperative points, analyzed with linear mixed-effects models. Postoperative nausea, vomiting, and neurological symptoms were assessed within 24 hours.

Main Results:

• Baseline ONSD was similar between groups.
• Both groups showed significant time-dependent ONSD changes (P < 0.001) with a significant group-by-time interaction (P < 0.001).
• TLH demonstrated greater ONSD increases than vNOTES at 30 minutes post-pneumoperitoneum (mean difference -0.14 mm) and at the end of surgery (mean difference -0.19 mm). Postoperative nausea and vomiting were more frequent in the TLH group (54.5% vs. 36.4%), but this did not reach statistical significance (P = 0.138).

Conclusions:

• Total laparoscopic hysterectomy (TLH) is linked to more significant intraoperative increases in optic nerve sheath diameter (ONSD) compared to vNOTES, likely due to surgical and positional factors.
• While postoperative outcomes were statistically similar, the trend towards higher nausea and vomiting in the TLH group warrants cautious interpretation and further investigation.
• vNOTES may offer a neuroprotective advantage by potentially mitigating intracranial pressure elevation during hysterectomy.