Optic Nerve Sheath DiameterNCT06994481
Comparison of the Effects of Endotracheal Intubation and Laryngeal Mask Applications on Optic Nerve Diameter in Pediatric Patients
An observational study of Optic Nerve Sheath Diameter and Pediatric Anesthesia, run by Marmara University Pendik Training and Research Hospital at 1 site in Turkey (Türkiye).
Trial summary
This clinical study aims to investigate the effects of breathing tubes - used to connect children aged 1-11 to a respiratory device under general anesthesia in the operating room - on intracranial pressure after they are inserted. Read more about this study
- Who is it for?
- Ages 1 year to 11 yearsHealthy volunteers can take part
- Conditions the study is for
- Optic Nerve Sheath Diameter, Pediatric Anesthesia, Intubation
- What is being tested?
- optic nerve sheet diameter measurement
- How many people
- 160 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 1 Sep 2025to 1 Aug 2026
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 1 year to 11 years
- All sexes
- Healthy volunteers accepted
- Child
Study population: ASA I-II children aged 1-11 years who are planned to receive general anesthesia, intubation or LMA insertion will be included in the study.
Who may be able to join
- Classified as American Society of Anesthesiologists (ASA) physical status I or II,
- Aged between 1 and 11 years,
- Scheduled to receive general anesthesia,
- Planned to be ventilated via endotracheal intubation or laryngeal mask airway (LMA).
Who cannot join
- Families who do not provide informed consent,
- Patients with a tracheostomy,
- History of previous intracranial surgery (e.g., tumor resection or shunt placement),
- History of preoperative seizures,
- Presence of craniofacial deformities that may prevent accurate optic nerve sheath diameter (ONSD) measurement,
- Infection, wound, or any other condition in the measurement area that may interfere with ONSD assessment,
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- Presence of conditions that may increase intracranial pressure and affect ONSD measurement (e.g., tumor, encephalitis, meningitis, or intracranial infection),
- Patients who require a change in the endotracheal tube or laryngeal mask airway (LMA) size during the operation, or who undergo a second intubation or insertion attempt,
- Patients who withdraw from the study.
Trial locations and contacts
1 site in 1 country.
Turkey (Türkiye)1 site
Marmara University Pendik Eğitim Ve Araştırma Hastanesi
Istanbul
About this study
This clinical study aims to investigate the effects of breathing tubes - used to connect children aged 1-11 to a respiratory device under general anesthesia in the operating room - on intracranial pressure after they are inserted. No changes will be made to routine anesthesia practices for this purpose, and eye examinations will be performed with an ultrasound (USG) device. This study has no undesirable effects or risks. This study does not include any invasive procedures. Participants have the right to refuse to take part in the study. Participants have the right to withdraw from the study at any time. If a participant decides not to take part in the study for any reason, there will be no disruption to that participant's treatment. Participants will not incur any financial loss by taking part in the study and will not be paid. Each participant's identity will be kept confidential throughout participation in the study.
Read the detailed description
The study will be conducted in the Marmara University Pendik Training and Research Hospital, Prof. Dr. Asaf Ataseven Additional Service Building Operating Room, on 160 ASA 1-2 (American Society of Anesthesiologists) children aged 1-11 who will undergo elective surgery under general anesthesia, with informed consent forms obtained from their families. The patients will be divided into 2 groups of 80, aged 1-4 and 5-11, and each group will again be divided into two, with half receiving an LMA (laryngeal mask = supraglottic upper airway device) and the other half receiving an ETT (endotracheal tube), giving 40 participants per device in each age group. The demographic data (age, gender, height, weight) of the patients included in the study will be recorded in the study form. Pediatric patients included in the study will undergo standard ASA monitoring (ECG, SpO2, noninvasive blood pressure, EtCO2). After general anesthesia induction, intubation or LMA will be applied according to the anesthesiologist's decision. Anesthesia will be maintained with sevoflurane and remifentanil infusion in a mixture of 40% O2 and 60% air, and the inhaled sevoflurane concentration will be targeted to maintain the BIS score between 40 and 60. Peak inspiratory pressure will be kept between 11 and 13 cm H2O in order not to affect ICP. After covering the eyes of each patient with a sterile film sheet, a thick layer of water-soluble ultrasound transmission gel will be applied to the upper eyelid, then the probe will be gently placed on the eyelid without applying pressure. For sonographic measurements, a linear 6-13 MHz probe (MyLab Seven, Esaote, Genova, Italy) will be used at three different time points. The probe will be carefully moved to find the best image of the optic nerve entering the globe, and ONSD (optic nerve sheath diameter) will be measured 3 mm posterior to the globe. These measurements will be taken at 3 times: (T0) immediately after anesthesia induction, (T1) within a few minutes after endotracheal intubation / LMA insertion, and (T2) immediately after extubation. At the specified times, ultrasonographic measurements will be made and recorded by 2 different individuals who have received USG training and who have previously measured the optic nerve sheath diameter. Mean arterial pressure and EtCO2 values will also be recorded simultaneously.
- Being tested
- optic nerve sheet diameter measurement
- Keywords
- optic nerve sheath diameter, pediatric patients, intubation, laryngeal mask airway
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
optic nerve sheet diameter measurementDiagnostic test
Optic nerve sheath diameter will be measured noninvasively using a 6-13 MHz linear ultrasound probe placed gently over the closed upper eyelid without applying pressure to the globe. Measurements will be obtained 3 mm posterior to the globe in both eyes at three predefined time points:
T0: Immediately after induction of general anesthesia and before airway device placement T1: Within the first few minutes after endotracheal tube or laryngeal mask airway placement T2: Immediately after removal of the airway device at the end of anesthesia Mean arterial pressure and end-tidal carbon dioxide values will be recorded simultaneously.
| Study group | Role | What they receive |
|---|---|---|
| 5-11 Years - Laryngeal Mask Airway | This group includes 40 children aged 5-11 years undergoing elective surgery under general anesthesia with airway management using a laryngeal mask airway. The airway management method is selected by the attending anesthesiologist as part of routine clinical care. Optic nerve sheath diameter is measured ultrasonographically at predefined perioperative time points. Receives: Diagnostic Test: optic nerve sheet diameter measurement | |
| 1-4 Years - Endotracheal Intubation | This group includes 40 children aged 1-4 years undergoing elective surgery under general anesthesia with airway management using endotracheal intubation. The airway management method is selected by the attending anesthesiologist as part of routine clinical care. Optic nerve sheath diameter is measured ultrasonographically at predefined perioperative time points. Receives: Diagnostic Test: optic nerve sheet diameter measurement | |
| 1-4 Years - Laryngeal Mask Airway | This group includes 40 children aged 1-4 years undergoing elective surgery under general anesthesia with airway management using a laryngeal mask airway. The airway management method is selected by the attending anesthesiologist as part of routine clinical care. Optic nerve sheath diameter is measured ultrasonographically at predefined perioperative time points. Receives: Diagnostic Test: optic nerve sheet diameter measurement | |
| 5-11 Years - Endotracheal Intubation | This group includes 40 children aged 5-11 years undergoing elective surgery under general anesthesia with airway management using endotracheal intubation. The airway management method is selected by the attending anesthesiologist as part of routine clinical care. Optic nerve sheath diameter is measured ultrasonographically at predefined perioperative time points. Receives: Diagnostic Test: optic nerve sheet diameter measurement |
What is being measured
The primary outcome is the main question the study is designed to answer.
optic nerve sheet diameter measurement
For sonographic measurements, a linear 6-13 Hz probe (Fujifilm Sonosite, Bothwell, USA) will be used at three different time points. The probe will be carefully moved to find the best image of the optic nerve entering the globe, and ONSD (optic nerve sheath diameter) will be measured 3 mm posterior to the globe. These measurements will be taken at 3 times: (TO) immediately after anesthesia induction, (T1) within a few minutes after endotracheal intubation / LMA insertion, and (T2) immediately after extubation.
At the specified times, ultrasonographic measurements will be made and recorded by 2 different individuals who have received USG training and who have previously measured the optic nerve sheath diameter. Mean arterial pressure and EtCO2 values will also be recorded simultaneously.
Measured: (TO) immediately after anesthesia induction, (T1) within a few minutes after endotracheal intubation / LMA insertion, (T2) immediately after extubation.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted29 May 2025
- Study start1 Sep 2025
- Primary completion1 Aug 2026
- Study completion1 Aug 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Optic Nerve Sheath DiameterStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Case-control
- Time perspective
- Prospective
- Enrolment
- 160 participants (actual)
Sponsor and investigators
- Lead sponsor
- Marmara University Pendik Training and Research Hospital
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, dilara gocmen, Marmara University Pendik Training and Research Hospital
- Investigators
- tümay umuroglu, professor doctor, Study director, Marmara University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06994481
- Sponsor's protocol ID
- marmaraeah1
- Status last verified
- Oct 2026
- First submitted
- 20 May 2025
- Last updated
- 7 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes
Study at a glance
From the registry record, last updated by the sponsor on 7 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Comparison of the Effects of Endotracheal Intubation and Laryngeal Mask Applications on Optic Nerve Diameter in Pediatric Patients
- ClinicalTrials.gov ID
- NCT06994481
- Acronym / sponsor ID
- marmaraeah1
- Keywords
- optic nerve sheath diameter, pediatric patients, intubation, laryngeal mask airway
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 160 participants (actual)
- Lead sponsor
- Marmara University Pendik Training and Research HospitalUniversity, hospital or other
- Study start
- 1 Sep 2025 (actual)
- Primary completion
- 1 Aug 2026 (actual)
- Study completion
- 1 Aug 2026 (actual)
- First posted
- 29 May 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This clinical study aims to investigate the effects of breathing tubes - used to connect children aged 1-11 to a respiratory device under general anesthesia in the operating room - on intracranial pressure after they are inserted. No changes will be made to routine anesthesia practices for this purpose, and eye examinations will be performed with an ultrasound (USG) device. This study has no undesirable effects or risks. This study does not include any invasive procedures. Participants have the right to refuse to take part in the study. Participants have the right to withdraw from the study at any time. If a participant decides not to take part in the study for any reason, there will be no disruption to that participant's treatment. Participants will not incur any financial loss by taking part in the study and will not be paid. Each participant's identity will be kept confidential throughout participation in the study.
Detailed description
The study will be conducted in the Marmara University Pendik Training and Research Hospital, Prof. Dr. Asaf Ataseven Additional Service Building Operating Room, on 160 ASA 1-2 (American Society of Anesthesiologists) children aged 1-11 who will undergo elective surgery under general anesthesia, with informed consent forms obtained from their families. The patients will be divided into 2 groups of 80, aged 1-4 and 5-11, and each group will again be divided into two, with half receiving an LMA (laryngeal mask = supraglottic upper airway device) and the other half receiving an ETT (endotracheal tube), giving 40 participants per device in each age group. The demographic data (age, gender, height, weight) of the patients included in the study will be recorded in the study form. Pediatric patients included in the study will undergo standard ASA monitoring (ECG, SpO2, noninvasive blood pressure, EtCO2). After general anesthesia induction, intubation or LMA will be applied according to the anesthesiologist's decision. Anesthesia will be maintained with sevoflurane and remifentanil infusion in a mixture of 40% O2 and 60% air, and the inhaled sevoflurane concentration will be targeted to maintain the BIS score between 40 and 60. Peak inspiratory pressure will be kept between 11 and 13 cm H2O in order not to affect ICP. After covering the eyes of each patient with a sterile film sheet, a thick layer of water-soluble ultrasound transmission gel will be applied to the upper eyelid, then the probe will be gently placed on the eyelid without applying pressure. For sonographic measurements, a linear 6-13 MHz probe (MyLab Seven, Esaote, Genova, Italy) will be used at three different time points. The probe will be carefully moved to find the best image of the optic nerve entering the globe, and ONSD (optic nerve sheath diameter) will be measured 3 mm posterior to the globe. These measurements will be taken at 3 times: (T0) immediately after anesthesia induction, (T1) within a few minutes after endotracheal intubation / LMA insertion, and (T2) immediately after extubation. At the specified times, ultrasonographic measurements will be made and recorded by 2 different individuals who have received USG training and who have previously measured the optic nerve sheath diameter. Mean arterial pressure and EtCO2 values will also be recorded simultaneously.
Study design
- Observational model
- Case-control
- Time perspective
- Prospective
- Number of arms
- 4
| Arm | Type | Receives |
|---|---|---|
| 5-11 Years - Laryngeal Mask Airway | – | Diagnostic Test: optic nerve sheet diameter measurementThis group includes 40 children aged 5-11 years undergoing elective surgery under general anesthesia with airway management using a laryngeal mask airway. The airway management method is selected by the attending anesthesiologist as part of routine clinical care. Optic nerve sheath diameter is measured ultrasonographically at predefined perioperative time points. |
| 1-4 Years - Endotracheal Intubation | – | Diagnostic Test: optic nerve sheet diameter measurementThis group includes 40 children aged 1-4 years undergoing elective surgery under general anesthesia with airway management using endotracheal intubation. The airway management method is selected by the attending anesthesiologist as part of routine clinical care. Optic nerve sheath diameter is measured ultrasonographically at predefined perioperative time points. |
| 1-4 Years - Laryngeal Mask Airway | – | Diagnostic Test: optic nerve sheet diameter measurementThis group includes 40 children aged 1-4 years undergoing elective surgery under general anesthesia with airway management using a laryngeal mask airway. The airway management method is selected by the attending anesthesiologist as part of routine clinical care. Optic nerve sheath diameter is measured ultrasonographically at predefined perioperative time points. |
| 5-11 Years - Endotracheal Intubation | – | Diagnostic Test: optic nerve sheet diameter measurementThis group includes 40 children aged 5-11 years undergoing elective surgery under general anesthesia with airway management using endotracheal intubation. The airway management method is selected by the attending anesthesiologist as part of routine clinical care. Optic nerve sheath diameter is measured ultrasonographically at predefined perioperative time points. |
Who may qualify
- Ages
- 1 year to 11 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Child
- Study population
- ASA I-II children aged 1-11 years who are planned to receive general anesthesia, intubation or LMA insertion will be included in the study.
Key inclusion criteria (4 listed)
- Classified as American Society of Anesthesiologists (ASA) physical status I or II,
- Aged between 1 and 11 years,
- Scheduled to receive general anesthesia,
- Planned to be ventilated via endotracheal intubation or laryngeal mask airway (LMA).
Key exclusion criteria (9 listed)
- Families who do not provide informed consent,
- Patients with a tracheostomy,
- History of previous intracranial surgery (e.g., tumor resection or shunt placement),
- History of preoperative seizures,
- Presence of craniofacial deformities that may prevent accurate optic nerve sheath diameter (ONSD) measurement,
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| optic nerve sheet diameter measurementOptic nerve sheath diameter will be measured noninvasively using a 6-13 MHz linear ultrasound probe placed gently over the closed upper eyelid without applying pressure to the globe. Measurements will be obtained 3 mm posterior to the globe in both eyes at three predefined time points: T0: Immediately after induction of general anesthesia and before airway device placement T1: Within the first few minutes after endotracheal tube or laryngeal mask airway placement T2: Immediately after removal of the airway device at the end of anesthesia Mean arterial pressure and end-tidal carbon dioxide values will be recorded simultaneously. | Diagnostic test | 1-4 Years - Endotracheal Intubation, 1-4 Years - Laryngeal Mask Airway, 5-11 Years - Endotracheal Intubation, 5-11 Years - Laryngeal Mask Airway |
Primary outcome
optic nerve sheet diameter measurement
Time frame: (TO) immediately after anesthesia induction, (T1) within a few minutes after endotracheal intubation / LMA insertion, (T2) immediately after extubation.
For sonographic measurements, a linear 6-13 Hz probe (Fujifilm Sonosite, Bothwell, USA) will be used at three different time points. The probe will be carefully moved to find the best image of the optic nerve entering the globe, and ONSD (optic nerve sheath diameter) will be measured 3 mm posterior to the globe. These measurements will be taken at 3 times: (TO) immediately after anesthesia induction, (T1) within a few minutes after endotracheal intubation / LMA insertion, and (T2) immediately after extubation. At the specified times, ultrasonographic measurements will be made and recorded by 2 different individuals who have received USG training and who have previously measured the optic nerve sheath diameter. Mean arterial pressure and EtCO2 values will also be recorded simultaneously.
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 7 Oct 2026.
- Individual participant dataSharing planned: Yes
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
tümay umuroglu, professor doctor study director
Marmara University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Optic Nerve Sheath Diameter and Pediatric Anesthesia, run by Marmara University Pendik Training and Research Hospital at 1 site in Turkey (Türkiye).
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 9 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 7 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Turkey (Türkiye). Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
optic nerve sheet diameter measurement (time frame: (TO) immediately after anesthesia induction, (T1) within a few minutes after endotracheal intubation / LMA insertion, (T2) immediately after extubation.). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 7 Oct 2026.