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Transorbital Ultrasound of Optic Nerve Sheath Diameter Between Healthy Pregnant Women and Those With Severe Preeclampsia.

Transorbital Ultrasound Measurement of Optic Nerve Sheath Diameter Between Pregnant Women With Severe Preeclampsia and Normal Gestations. Prospective, Controlled Trial.

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05594056
Enrollment
100
Registered
2022-10-26
Start date
2022-10-21
Completion date
2023-01-31
Last updated
2023-04-27

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Preeclampsia Severe

Keywords

Severe preeclampsia, Optic nerve sheet, Intracranial pressure

Brief summary

The neurological alterations associated with preeclampsia depend on cerebral autoregulation, a theory that outlines the mechanisms by which the nervous system controls cerebral perfusion. However, with the loss of autoregulation, increased blood flow, edema and eventually increased intracranial pressure are triggered and may be translated into neurological manifestations such as symptoms of vasospasm, one of the criteria for severity in preeclampsia. Nervous system manifestations frequently found in preeclampsia are headache, blurred vision, scotomas and hyperreflexia. Although uncommon, temporary blindness (lasting a few hours to a week) may also accompany severe preeclampsia and eclampsia. The optic nerve, as part of the central nervous system, is surrounded by cerebrospinal fluid and dura mater, which forms the optic nerve sheath. Due to the connection with the intracranial subarachnoid space, the diameter of the optic nerve sheath is influenced by variations in cerebrospinal fluid pressure. Increased intracranial pressure is transmitted to the subarachnoid space surrounding the optic nerve, causing its expansion. Recent studies suggest that an optic nerve sheath diameter greater than 5 mm correlates 100% with ICP (intracerebral pressure) greater than 20 mm Hg. Due to the simple nature of the test and the limited time required to perform it, it is an ideal non-invasive test to assess changes in mental status, severe headache, and to take the necessary measures aimed at reducing intracranial pressure. The diagnosis of elevated intracranial pressure is challenging and critical, because early recognition and treatment are essential to prevent brain damage or death since preeclampsia with severe data remains one of the most frequent complications in our institution. These values are not taken from the obstetric population, so this study proposes the description of a standard value for the pregnant population. There are few studies that describe a value to help us define cases of this pathology and correlate it with the signs and symptoms of severity in patients with preeclampsia.

Interventions

PROCEDURETransorbital ultrasound of the optic nerve sheet

Measurement of the optic nerve sheet with a linear transducer (7,5 MHz).

Sponsors

Saint Thomas Hospital, Panama
Lead SponsorOTHER

Study design

Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
DIAGNOSTIC
Masking
NONE

Intervention model description

A transorbital ultrasound to measure the optic nerve sheet will be performed in patients with severe preeclampsia and then compared with normal controls.

Eligibility

Sex/Gender
FEMALE
Age
15 Years to 44 Years
Healthy volunteers
No

Inclusion criteria

* Age between 15-44 years. * Gestational age between 34-40 weeks of gestation.

Exclusion criteria

* Eye disease (Glaucoma, diabetic neuropathy, optic neuritis). * Nervous disorders. * Psychiatric disorders * Diabetes

Design outcomes

Primary

MeasureTime frameDescription
Optic nerve sheet measurement24 hoursThe diameter of the optic nerve sheath was measured three millimeters behind the eyeball, and one axis perpendicular to the optic nerve. Three measurements were taken in each eye. The resulting six measurements were averaged to give a mean of the optic nerve sheet measurement, to minimize measurement variability.

Countries

Panama

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026