Assessment of Optic Sheat Diameter (ONSD) and Eyeball Transverse Diameter (ETD) Ratio Measurement From Ocular Ultrasound

NCT07784361 | Not Yet Recruiting

• 1 other identifier: 2024-KAEK-39
• Study Type: observational
• Target: 68
• Locations: 0 countries
• Sites: N/A

Brief Summary

The aim of this study is to evaluate the effects of different carbon dioxide gas insufflation pressures on the ultrasound-guided optic nerve sheath diameter in patients undergoing laparoscopic cholecystectomy and to determine the possible relationship between these changes and intracranial pressure. The study aims to gain a better understanding of the neurophysiological effects of gas pressures used during laparoscopic surgery and to obtain scientific data aimed at improving patient safety.

Conditions

Optic Nerve Sheath Diameter Measurement; Intracranial Pressure Increase; Laparoscopic Cholecystectomy Surgery

Keywords

ONSD; ETD; Laparoscopic Cholecystectomy; intracranial pressure increase

Outcome Measures

Primary Outcomes (1)

• ONSD/ETD

  Optic nerve sheath diameter (ONSD) eyeball transverse diameter (ETD) ratio: The ONSD/ETD ratio will be calculated by dividing the mean ONSD value by the mean ETD value for each participant. This dimensionless ratio will be utilized as a standardized surrogate marker to evaluate changes in intracranial pressure (ICP), effectively minimizing confounding individual variations in eyeball size and ocular anatomy

  T1(Baseline):Before the induction of anesthesia T2(Post-Intubation):5 minutes after endotracheal intubation T3(Intra-Pneumoperitoneum):15 minutes after the establishment of pneumoperitoneum T4(Post-Exsufflation):10 minutes after complete Exsufflation

Secondary Outcomes (2)

• ONSD

  T1(Baseline):Before the induction of anesthesia T2(Post-Intubation):5 minutes after endotracheal intubation T3(Intra-Pneumoperitoneum):15 minutes after the establishment of pneumoperitoneum T4(Post-Exsufflation):10 minutes after complete Exsufflation

• MAP

  T1(Baseline):Before the induction of anesthesia T2(Post-Intubation):5 minutes after endotracheal intubation T3(Intra-Pneumoperitoneum):15 minutes after the establishment of pneumoperitoneum T4(Post-Exsufflation):10 minutes after complete Exsufflation

Study Arms (1)

Laparoscopic Cholecystectomy

Observation of patients undergoing laparoscopic cholecystectomy under either low or high gas insufflation pressure determined by the clinical routine. Optic nerve sheath diameter (ONSD) and eyeball transverse diameter (ETD) will be measured via non-invasive transorbital ultrasonography.

Procedure: Low Pressure Group; Procedure: High Pressure Group

Interventions

Low Pressure Group PROCEDURE

Data will be collected on patients who underwent surgery within a pressure range of 10-14, depending on the surgeon's preference.

Laparoscopic Cholecystectomy

High Pressure Group PROCEDURE

Data will be collected on patients who underwent surgery within a pressure range of 14-18, depending on the surgeon's preference.

Laparoscopic Cholecystectomy

Eligibility Criteria

• Age: 18 Years - 80 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

The study population consists of adult patients aged 18-80 years, classified as ASA I-II physical status, who are scheduled to undergo elective laparoscopic cholecystectomy in a tertiary care hospital setting. Patients are observed within the routine clinical workflow of the anesthesia and general surgery departments.

You may qualify if:

• Patients aged between 18 and 80 years.
• Patients scheduled for laparoscopic cholecystectomy.
• ASA (American Society of Anesthesiologists) physical status I or II.

You may not qualify if:

• History of intracranial space-occupying lesion or high intracranial pressure (ICP).
• History of abdominal trauma.
• History of orbital/ocular trauma.

Sponsors & Collaborators

• Gaziantep City Hospital: lead

Related Publications (2)

• Huang Y, Cai Y, Peng MQ, Yi TT. Evaluation of the effect of fluid management on intracranial pressure in patients undergoing laparoscopic gynaecological surgery based on the ratio of the optic nerve sheath diameter to the eyeball transverse diameter as measured by ultrasound: a randomised controlled trial. BMC Anesthesiol. 2024 Sep 7;24(1):319. doi: 10.1186/s12871-024-02683-7.

  PMID: 39244545 RESULT

• Kim EJ, Koo BN, Choi SH, Park K, Kim MS. Ultrasonographic optic nerve sheath diameter for predicting elevated intracranial pressure during laparoscopic surgery: a systematic review and meta-analysis. Surg Endosc. 2018 Jan;32(1):175-182. doi: 10.1007/s00464-017-5653-3. Epub 2017 Jun 21.

  PMID: 28639043 RESULT

MeSH Terms

Conditions

Intracranial Hypertension

Condition Hierarchy (Ancestors)

Brain Diseases; Central Nervous System Diseases; Nervous System Diseases

Central Study Contacts

Gamze Nur Teke, medical doctor

CONTACT

+905546694389; gamzenur.koca@gmail.com

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: medical doctor

Study Record Dates

• First Submitted: August 18, 2026
• First Posted: August 25, 2026
• Study Start: August 30, 2026
• Primary Completion (Estimated): October 15, 2026
• Study Completion (Estimated): October 30, 2026
• Last Updated: August 25, 2026

Record last verified: 2026-08

Data Sharing

• IPD Sharing: Will not share