General AnesthesiaNCT07199049
Neuro-Mimic Indicators of Anesthesia Depth During General Anesthesia
An observational study of General Anesthesia and Intraoperative Awareness, run by Başakşehir Çam & Sakura City Hospital at 1 site in Turkey (Türkiye).
Trial summary
This prospective observational study will evaluate neuro-mimic indicators of anesthesia depth, including eyelid reflex, eyeball movements, and pupil responses, in patients undergoing elective surgery under general anesthesia. Read more about this study
- Who is it for?
- Ages 18 to 65 yearsHealthy volunteers can take part
- Conditions the study is for
- General Anesthesia, Intraoperative Awareness, Eye Movements
- What is being tested?
- Neuro-Mimic Observation Protocol
- How many people
- 125 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 15 Dec 2025to 15 Jul 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 18 to 65 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Study population: Adult patients aged 18-65 years, ASA physical status I-III, undergoing elective abdominal surgery under general anesthesia at Başakşehir Çam and Sakura City Hospital will be included. Eligible patients must have the eye area uncovered and in a position suitable for observation, with surgery expected to last 1-3 hours. Both male and female patients will be enrolled. Head, neck, and eye surgeries or cases requiring full draping of the eye area will be excluded.
Who may be able to join
- The study will include patients aged 18-65 who will undergo elective abdominal surgery (e.g., cholecystectomy/gastrectomy/colorectal surgery/prostatectomy/hysterectomy, etc.) under general anesthesia, with a planned duration of 1-3 hours.
- Patients whose eye area is left uncovered and who are in a position suitable for observation
- Patients who have signed the informed consent form
- Patients with an ASA score of I-III
Who cannot join
- Patients undergoing surgical procedures in the head, neck, or face region (e.g., ENT, eye, jaw surgery, neurosurgery, thyroid/parathyroid)
- Patients whose eye area must be completely covered with a sterile drape
- Patients with an ASA score of IV or higher
- Individuals with neurological disorders and impaired pupil response, patients who have previously undergone eye trauma or surgery and cannot undergo pupil evaluation
- Patients who are unable to communicate and cannot provide informed consent
- Emergency surgeries (e.g., appendectomy/ileus/gastrointestinal perforation/cesarean section/gunshot wounds/stab wounds/multiple trauma/traffic accidents, etc.)
- Individuals who have previously been included in this study (to prevent repeated inclusion)
Trial locations and contacts
1 site in 1 country.
Turkey (Türkiye)1 site
Başakşehir Çam and Sakura City Hospital
Başakşehir, Istanbul, 34480
About this study
Official title: Monitoring Eyelid Reflex, Eye Movements, and Pupil Responses in Patients Undergoing General Anesthesia: Neuro-Mimic Indicators of Anesthesia Depth
This prospective observational study will evaluate neuro-mimic indicators of anesthesia depth, including eyelid reflex, eyeball movements, and pupil responses, in patients undergoing elective surgery under general anesthesia. Sixty adult patients will be observed at three standardized time points: after induction, during skin incision, and mid-surgery. All parameters will be recorded alongside bispectral index (BIS) monitoring. The study aims to determine whether these observable signs correlate with anesthesia depth, contribute to early detection of intraoperative awareness, and provide a basis for developing non-invasive depth monitoring systems.
Read the detailed description
Accurate assessment of anesthesia depth is essential to ensure patient safety and reduce the risk of intraoperative awareness. Current technological monitoring tools such as BIS do not always provide sufficient reliability. Neuro-mimic indicators, including eyelid reflex, spontaneous and stimulus-related eye movements, and pupil responses, may offer additional insights into anesthesia depth. This observational, prospective, non-interventional study will enroll 60 adult patients (aged 18-65, ASA I-III) scheduled for elective abdominal surgeries lasting 1-3 hours under general anesthesia at Başakşehir Çam and Sakura City Hospital. Observations will be performed at three intraoperative stages: post-induction, skin incision, and mid-surgery. Parameters include palpebral reflex, eyeball position and movement, and pupil diameter, all systematically documented alongside BIS values. The primary endpoint is the change in pupil diameter across three time points. Secondary outcomes include the presence or absence of eyelid reflex, eye movements, and their correlations with BIS values. Data will be analyzed using repeated measures ANOVA, McNemar test, correlation analyses, and appropriate non-parametric tests where necessary. The study is entirely observational and involves no additional interventions or risks for patients. Results may provide evidence for the integration of observable physiological signs into anesthesia monitoring practice and contribute to the development of contactless depth monitoring systems.
- Conditions
- General Anesthesia, Intraoperative Awareness, Eye Movements
- Being tested
- Neuro-Mimic Observation Protocol
- Keywords
- Anesthesia, General, Awareness, Intraoperative, Pupillary Reflex, Eye Movements, Reflex, Blink (Eyelid Reflex)
- Medical subject headings
- Intraoperative Awareness
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Neuro-Mimic Observation ProtocolOther
Also called Eyelid Reflex Monitoring, Eye Movement Observation, Pupil Diameter Assessment
Observation of eyelid reflex, eye movements, and pupil responses at three standardized intraoperative time points (after induction, during skin incision, and mid-surgery). Parameters will be recorded alongside BIS values without any intervention, device application, or additional risk to patients.
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in pupil diameter during general anesthesia
Pupil diameter (mm) will be measured and compared at three intraoperative stages: after induction and intubation, during skin incision, and mid-surgery. The change over time will be analyzed as an indicator of anesthesia depth.
Measured: Intraoperative period (observations at induction, incision, and mid-surgery).
Secondary outcomes (4)
Presence or absence of eyelid reflex at different anesthesia stages
Eyelid reflex (palpebral reflex) will be assessed as present or absent at three intraoperative stages and analyzed in relation to anesthesia depth.
Measured: Intraoperative period (induction, incision, mid-surgery).
Eye position and movements during anesthesia
Eyeball position (central, upward, downward, eccentric) and spontaneous movements will be observed and documented at three time points. Changes will be evaluated as neuro-mimic indicators of anesthesia depth.
Measured: Intraoperative period (induction, incision, mid-surgery).
Correlation of neuro-mimic indicators with BIS values
Observed eyelid reflex, eye movements, and pupil responses will be correlated with simultaneously recorded BIS values to explore associations with anesthesia depth.
Measured: Intraoperative period (induction, incision, mid-surgery).
Early indicators of intraoperative awareness
The relationship between observed neuro-mimic responses (eyelid reflex, eye movements, pupil diameter) and intraoperative awareness risk will be evaluated descriptively.
Measured: Intraoperative period.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted30 Sep 2025
- Study start15 Dec 2025
- Primary completion25 Jun 2026
- Study completion15 Jul 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (4)Papers the sponsor has linked to this study.
- Other trials for General AnesthesiaStudies 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
- Cohort
- Time perspective
- Prospective
- Enrolment
- 125 participants (actual)
Sponsor and investigators
- Lead sponsor
- Başakşehir Çam & Sakura City Hospital
- Sponsor type
- Other government
- Responsible party
- Principal investigator, Emine OZCAN, Başakşehir Çam & Sakura City Hospital
- Investigators
- Emine Ozcan, MD, Principal investigator, Başakşehir Çam & Sakura City Hospital
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07199049
- Sponsor's protocol ID
- NEURO3419
- Status last verified
- Jul 2026
- First submitted
- 22 Sep 2025
- Last updated
- 22 Jul 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: Individual participant data (IPD) will not be shared due to privacy and confidentiality concerns. Only summary-level data and aggregated results will be published in scientific journals or presented at conferences.
Publications
Ben Barak-Dror O, Hadad B, Barhum H, Haggiag D, Tepper M, Gannot I, Nir Y. Touchless short-wave infrared imaging for dynamic rapid pupillometry and gaze estimation in closed eyes. Commun Med (Lond). 2024 Aug 6;4(1):157. doi: 10.1038/s43856-024-00572-1.
PubMed 39107497Singh A, Akhileshwar, Kumar N, De RR, Bahadur R, Shekhar S. The Role of Pupillometry in the Assessment of Pain in Children Under General Anesthesia: A Prospective Single-Blinded Observational Study. Cureus. 2023 Aug 22;15(8):e43894. doi: 10.7759/cureus.43894. eCollection 2023 Aug.
PubMed 37753025Chaurasia S, Soni SL, Ganesh V, Ram J, Sukhija J, Chaurasia S, Takkar A. Tonic down-rolling and eccentric down-positioning of eyes under sevoflurane anesthesia without non-depolarizing muscle relaxant and its relationship with depth of anesthesia. Front Med (Lausanne). 2023 Jun 15;10:1029952. doi: 10.3389/fmed.2023.1029952. eCollection 2023.
PubMed 37396902Xing L, Xie H, Zhou X, Zhu J, Liu H. Ultrasound Measurement of Pupillary Dilation Reflex During Induction of General Anesthesia Using Sufentanil: A Randomized Controlled Trial. Med Sci Monit. 2025 Jun 23;31:e948209. doi: 10.12659/MSM.948209.
PubMed 40549665
Study at a glance
From the registry record, last updated by the sponsor on 22 Jul 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Monitoring Eyelid Reflex, Eye Movements, and Pupil Responses in Patients Undergoing General Anesthesia: Neuro-Mimic Indicators of Anesthesia Depth
- ClinicalTrials.gov ID
- NCT07199049
- Acronym / sponsor ID
- NEURO3419
- Conditions
- General Anesthesia, Intraoperative Awareness, Eye Movements
- Keywords
- Anesthesia, General, Awareness, Intraoperative, Pupillary Reflex, Eye Movements, Reflex, Blink (Eyelid Reflex)
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 125 participants (actual)
- Lead sponsor
- Başakşehir Çam & Sakura City HospitalOther government
- Study start
- 15 Dec 2025 (actual)
- Primary completion
- 25 Jun 2026 (actual)
- Study completion
- 15 Jul 2026 (actual)
- First posted
- 30 Sep 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 prospective observational study will evaluate neuro-mimic indicators of anesthesia depth, including eyelid reflex, eyeball movements, and pupil responses, in patients undergoing elective surgery under general anesthesia. Sixty adult patients will be observed at three standardized time points: after induction, during skin incision, and mid-surgery. All parameters will be recorded alongside bispectral index (BIS) monitoring. The study aims to determine whether these observable signs correlate with anesthesia depth, contribute to early detection of intraoperative awareness, and provide a basis for developing non-invasive depth monitoring systems.
Detailed description
Accurate assessment of anesthesia depth is essential to ensure patient safety and reduce the risk of intraoperative awareness. Current technological monitoring tools such as BIS do not always provide sufficient reliability. Neuro-mimic indicators, including eyelid reflex, spontaneous and stimulus-related eye movements, and pupil responses, may offer additional insights into anesthesia depth. This observational, prospective, non-interventional study will enroll 60 adult patients (aged 18-65, ASA I-III) scheduled for elective abdominal surgeries lasting 1-3 hours under general anesthesia at Başakşehir Çam and Sakura City Hospital. Observations will be performed at three intraoperative stages: post-induction, skin incision, and mid-surgery. Parameters include palpebral reflex, eyeball position and movement, and pupil diameter, all systematically documented alongside BIS values. The primary endpoint is the change in pupil diameter across three time points. Secondary outcomes include the presence or absence of eyelid reflex, eye movements, and their correlations with BIS values. Data will be analyzed using repeated measures ANOVA, McNemar test, correlation analyses, and appropriate non-parametric tests where necessary. The study is entirely observational and involves no additional interventions or risks for patients. Results may provide evidence for the integration of observable physiological signs into anesthesia monitoring practice and contribute to the development of contactless depth monitoring systems.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
- Study population
- Adult patients aged 18-65 years, ASA physical status I-III, undergoing elective abdominal surgery under general anesthesia at Başakşehir Çam and Sakura City Hospital will be included. Eligible patients must have the eye area uncovered and in a position suitable for observation, with surgery expected to last 1-3 hours. Both male and female patients will be enrolled. Head, neck, and eye surgeries or cases requiring full draping of the eye area will be excluded.
Key inclusion criteria (4 listed)
- The study will include patients aged 18-65 who will undergo elective abdominal surgery (e.g., cholecystectomy/gastrectomy/colorectal surgery/prostatectomy/hysterectomy, etc.) under general anesthesia, with a planned duration of 1-3 hours.
- Patients whose eye area is left uncovered and who are in a position suitable for observation
- Patients who have signed the informed consent form
- Patients with an ASA score of I-III
Key exclusion criteria (7 listed)
- Patients undergoing surgical procedures in the head, neck, or face region (e.g., ENT, eye, jaw surgery, neurosurgery, thyroid/parathyroid)
- Patients whose eye area must be completely covered with a sterile drape
- Patients with an ASA score of IV or higher
- Individuals with neurological disorders and impaired pupil response, patients who have previously undergone eye trauma or surgery and cannot undergo pupil evaluation
- Patients who are unable to communicate and cannot provide informed consent
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 |
|---|---|---|
| Neuro-Mimic Observation ProtocolAlso: Eyelid Reflex Monitoring, Eye Movement Observation, Pupil Diameter AssessmentObservation of eyelid reflex, eye movements, and pupil responses at three standardized intraoperative time points (after induction, during skin incision, and mid-surgery). Parameters will be recorded alongside BIS values without any intervention, device application, or additional risk to patients. | Other | – |
Primary outcome
Change in pupil diameter during general anesthesia
Time frame: Intraoperative period (observations at induction, incision, and mid-surgery).
Pupil diameter (mm) will be measured and compared at three intraoperative stages: after induction and intubation, during skin incision, and mid-surgery. The change over time will be analyzed as an indicator of anesthesia depth.
4 secondary outcomes
Presence or absence of eyelid reflex at different anesthesia stages
Time frame: Intraoperative period (induction, incision, mid-surgery).
Eye position and movements during anesthesia
Time frame: Intraoperative period (induction, incision, mid-surgery).
Correlation of neuro-mimic indicators with BIS values
Time frame: Intraoperative period (induction, incision, mid-surgery).
Early indicators of intraoperative awareness
Time frame: Intraoperative period.
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 22 Jul 2026.
- Background: PubMed 39107497Ben Barak-Dror O, Hadad B, Barhum H, Haggiag D, Tepper M, Gannot I, Nir Y. Touchless short-wave infrared imaging for dynamic rapid pupillometry and gaze estimation in closed eyes. Commun Med (Lond). 2024 Aug 6;4(1):157. doi: 10.1038/s43856-024-00572-1.
- Background: PubMed 37753025Singh A, Akhileshwar, Kumar N, De RR, Bahadur R, Shekhar S. The Role of Pupillometry in the Assessment of Pain in Children Under General Anesthesia: A Prospective Single-Blinded Observational Study. Cureus. 2023 Aug 22;15(8):e43894. doi: 10.7759/cureus.43894. eCollection 2023 Aug.
- Background: PubMed 37396902Chaurasia S, Soni SL, Ganesh V, Ram J, Sukhija J, Chaurasia S, Takkar A. Tonic down-rolling and eccentric down-positioning of eyes under sevoflurane anesthesia without non-depolarizing muscle relaxant and its relationship with depth of anesthesia. Front Med (Lausanne). 2023 Jun 15;10:1029952. doi: 10.3389/fmed.2023.1029952. eCollection 2023.
- Background: PubMed 40549665Xing L, Xie H, Zhou X, Zhu J, Liu H. Ultrasound Measurement of Pupillary Dilation Reflex During Induction of General Anesthesia Using Sufentanil: A Randomized Controlled Trial. Med Sci Monit. 2025 Jun 23;31:e948209. doi: 10.12659/MSM.948209.
- Individual participant dataSharing planned: No. Individual participant data (IPD) will not be shared due to privacy and confidentiality concerns. Only summary-level data and aggregated results will be published in scientific journals or presented at conferences.
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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.
Emine Ozcan, MD principal investigator
Başakşehir Çam & Sakura City Hospital
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 General Anesthesia and Intraoperative Awareness, run by Başakşehir Çam & Sakura City 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 7 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 22 Jul 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?
Change in pupil diameter during general anesthesia (time frame: Intraoperative period (observations at induction, incision, and mid-surgery).). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT07199049, which also lists 4 linked publications.
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 22 Jul 2026; AzTrials last refreshed its copy on 6 Nov 2026.