An interventional study of optic nerve diameter in Optic Nerve Diameter and Intracranial Pressure Increase, sponsored by Bursa Yuksek Ihtisas Training and Research Hospital. Completed at 1 site in Turkey (Türkiye). Open to participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-02-12.
Sponsored by Bursa Yuksek Ihtisas Training and Research Hospital · Not applicable, Interventional, and Diagnostic
Studies exist to determine the effect of laparoscopic surgical procedures on increased intra-abdominal pressure; these studies include optic nerve sheath diameter (ONSD) measurement in various positions such as trendelenburg and prone, and the effect of the laryngoscope used in intubation on increased intracranial pressure. In these situations, changes in cerebral blood flow and intracranial pressure may occur due to impaired neck venous return. There are no studies in the literature regarding increased osd and consequently increased intracranial pressure in lateral head position.ultrasound for ONSD measurement is a non-invasive, rapid, and easily applicable method for diagnosing changes in intracranial pressure. In tympanoplasty surgeries, the head and neck remain in a lateral position, and venous return in the surgical field may sometimes be compressed due to the procedure. The aim of this study is to determine the effect of lateral head position and variables such as demographic data and surgical duration on increased intracranial pressure. Methods: Patients over 18 years of age, classified as asa ı and ıı, undergoing tympanoplasty surgery under general anesthesia in the lateral head and neck position will be included in the study. Patients' vital signs (arterial blood pressure, heart rate, spo2, and etco2) will be monitored regularly in the operating room before and after surgery. Demographic data (age, gender, weight, height), surgery duration, and postoperative complications will also be recorded. Anesthesia will be administered with 2-4 mg/kg propofol, 0.6 mg/kg rocuronium, and 1-2 mcg/kg fentanyl for induction, and sevoflurane for maintenance. Following intubation, onstitial lateral head and neck (onsd) measurements will be taken by the anesthesiologist at three time intervals (in transverse and sagittal planes). Both onsds will be recorded by ultrasound: T1: 5 minutes in the supine position, T2: at the end of the procedure with the head in the lateral position, and T3: before extubation in the supine position. Postoperative headache and neck pain will be inquired about after waking up and at 1., 6., and 24. hours later.
165 studies on the registry are indexed under Intracranial Hypertension; 36 are open to participants now.
This study's enrollment of 53 is close to the median of 50 across 81 interventional studies indexed under Intracranial Hypertension.
Browse Intracranial Hypertension studies →Bursa Yuksek Ihtisas Training and Research Hospital is the lead sponsor of 52 studies on the registry; 22 are open to participants now.
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Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The anaesthetists’ scale of health before surgery: I is healthy, II has a mild illness that is under control, III a severe one, IV a severe illness that is a constant threat to life. V and VI are used for the critically ill and for organ donors.
ASA physical status
The anaesthetists’ scale of health before surgery: I is healthy, II has a mild illness that is under control, III a severe one, IV a severe illness that is a constant threat to life. V and VI are used for the critically ill and for organ donors.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ONSD measurements were taken in three time intervals by the anesthesiologist: transverse and sagittal planes. Both ONSDs were recorded by ultrasound at T1: 5 min in supine position, T2: end of the procedure with head in lateral position, and T3: supine position before extubation.
Diagnostic Test: optic nerve diameter
optic nerve diameter measurement
The effect of lateral head position on intracranial pressure
The effect of lateral head positioning on intracranial pressure will be determined by measuring the diameter of the optic nerve sheath under ultrasound guidance.
Time frame: 2 years
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: Yes — The study protocol and results can be shared.
Supporting information: Study protocol
Ran from Jan 2020 to primary completion in Jul 2020, 6 months.
Of 37 non-industry interventional studies with no phase under Intracranial Hypertension, half reached primary completion within 15 months of starting (the median), counting those still running; a quarter within 6 and three quarters within 39. This study's 6 months is below that.
Counting every sponsor, half of 38 studies reached it within 18 months; a quarter within 6 and three quarters within 37.
How these figures are worked out, and which studies are left out of them.
This study is completed, as verified in Feb 2026. You cannot join it, but the record below documents what was studied.
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Bursa Yuksek Ihtisas Training and Research Hospital