Skip to main content
OpenTrials
Not Yet Recruiting

NCT Number: NCT07360756

Ultrasonographic ONSD as a Predictor of PDPH in Spinal Anesthesia for Cesarean Delivery

The Optic Nerve Sheath Diameter (ONSD), measured non-invasively by bedside ultrasound, is a well-established surrogate for intracranial pressure (ICP), as the optic nerve sheath is continuous with the intracranial dura mater and its subarachnoid space is filled with cerebrospinal fluid (CSF). While ONSD is typically used to detect elevated ICP (with a cut-off often > 5.0-5.7 mm for ICP > 20 mmHg), studies investigating PDPH have paradoxically shown a reduction in ONSD post-spinal anesthesia, correlating with the state of intracranial hypotension.

Previous research has demonstrated that a lower ONSD or a significant decrease in ONSD values 24 hours post-puncture is associated with PDPH development. A study determined that an ONSD at 24 hours of less than 0.40 cm was the best predictor for PDPH. Our study aims to specifically investigate the utility of the immediate change in ONSD to offer a bedside, real-time assessment of risk.

Not Yet Recruiting

Trial opening soon.

Get Notified

Key information

Conditions

Cesarean Section Complications Brain Diseases Central Nervous System Diseases Headache Disorders Headache Disorders, Secondary Nervous System Diseases Post-Dural Puncture Headache

Age range

18 year–45 year

Sex eligibility

Female

Study type

Observational

Primary location

Al-Azhar University

Cairo, Egypt, 11865

Location contact

Hany Baumy, M.D

PRINCIPAL_INVESTIGATOR

Neveen A. Kohaf, PhD

CONTACT

[email protected]

01060383012

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Adult female patients, aged 18-45 years
  • ASA(American Society of Anesthesiologists) physical status II or III
  • Scheduled for elective cesarean section
  • Undergoing surgery under standardized spinal anesthesia

Exclusion criteria

  • Pre-existing headache disorders (e.g., migraine, chronic tension-type headache)
  • Known ophthalmic conditions (e.g., optic neuropathy, glaucoma)
  • Inability to cooperate with ONSD(Optic Nerve Sheath Diameter) ultrasound measurements or follow-up
  • Allergy to local anesthetics
  • Emergency cesarean section
  • Contraindications to spinal anesthesia:
  • Coagulopathy
  • Infection at the puncture site
  • Preexisting hypertension on medication
  • Pre-eclampsia with severe features (suggested for separate study)
  • Known cardiac disease with hemodynamic instability
  • Allergy to study drugs
  • Fetal distress or non-reassuring cardiotocography (CTG)
  • Body Mass Index (BMI) >40 kg/m²
  • Refusal to sign informed consent

Treatment and study plan

Study Cohort (Single Cohort)

Procedure

This study comprises a single, prospectively enrolled cohort of 150 adult female patients (ASA physical status II-III) scheduled for elective cesarean section under standardized spinal anesthesia. All participants receive the same planned intervention (spinal anesthesia for surgery) and undergo the same standardized measurement protocol for Optic Nerve Sheath Diameter (ONSD). Within this cohort, participants are naturally divided by outcome during follow-up into two groups for analytical purposes:

PDPH-Positive Subgroup: Patients who develop Post-Dural Puncture Headache (PDPH) within 72 hours, as diagnosed using the International Classification of Headache Disorders (ICHD-3) criteria.

PDPH-Negative Subgroup: Patients who do not develop PDPH within the follow-up period.

Primary outcomes

  1. Optimal Delta ONSD cut-off value for predicting PDPH

    Time frame: 72 hours post-spinal.

    To determine the numerical value of the change in Optic Nerve Sheath Diameter (Delta ONSD = ONSD<sub>pre</sub> - ONSD<sub>post</sub>) that best predicts the development of PDPH.

Secondary outcomes

  1. Post-Dural Puncture Headache (PDPH)

    Time frame: 72h.

    To assess the intensity of headache pain. By Numeric Rating Scale (NRS):

    0 (no pain) to 10 (worst imaginable pain).

  2. The Need for Epidural Blood Patch (EBP)

    Time frame: 72 hour

    The % of patients requiring an Epidural Blood Patch will de determined

Study contacts

Contact information is provided by the study sponsor or research team.

Neveen A Kohaf, Ph.D

CONTACT

[email protected]

+201060383012

Sponsors and collaborators

Lead sponsor

Al-Azhar University

Other

Collaborators

  • Benha University

Registry information

Official study title

Early Prediction of Post-Dural Puncture Headache Using Ultrasound-Measured Optic Nerve Sheath Diameter in Cesarean Section Patients: A Prospective Observational Study

Important dates

Study start
2026
Primary completion
2026
Study completion
2026
First posted
Jan 22, 2026
Registry last updated
Jan 22, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.