Orbital Artery Doppler Ultrasound in Brain Death

Orbital Artery Doppler Ultrasound as an Ancillary Test for Diagnosing Brain Death: a Prospective, Single Blind Comparative Study

Brain death is the irreversible loss of all activity in the brain, brainstem, and cerebellum, the part of the central nervous system that remains inside the skull.

The clinical diagnosis of brain death should be supported by ancillary tests that provide information about cerebral blood flow or electrical activity in the brain. Some of the ancillary tests that evaluate cerebral blood flow include transcranial Doppler ultrasonography (TDUS), computed tomography (CT) angiography (CTA), and catheter-based cerebral angiography.

This study hypothesized that Orbital Doppler ultrasonography (ODUS) alone is more effective than TDUS in detecting intracranial blood flow in diagnosing brain death. To this end, the investigators examined the results of ODUS in patients diagnosed as brain dead who underwent CT angiography.

Study Overview

• Status: Completed
• Conditions: Brain Death
• Intervention / Treatment: Diagnostic test: Orbital Doppler ultrasonography; Diagnostic test: Transcranial Doppler ultrasonography; Diagnostic test: Computed Tomography Angiography

• Study Type: Interventional
• Enrollment (Actual): 66
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Turkey
  • Bursa, Turkey
    • University of Health Sciences,,Bursa Yuksek Ihtisas Training and Research Hospital,

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• suspected brain death

Exclusion Criteria:

• eye surgery,
• uncontrolled diabetes mellitus,
• facial trauma,
• hypothermia,
• hypotension (systolic pressure < 100 mm Hg)
• endocrine-metabolic coma

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Other: ODUS; Orbital Doppler ultrasonography (ODUS) Patients in whom brain death was suspected and the diagnostic procedure was initiated underwent ODUS .ODUS were performed during the apnoea test and the first neurological examination. At the second neurological examination at 12 hours, ODUS were repeated.

Diagnostic test: Orbital Doppler ultrasonography; During measurement, Doppler settings were adjusted to detect low flow and the smallest available Doppler gate was used for all ODUS examinations. The imaging probe position for ODUS was used transversely and axially, and mean values were recorded. ODUS 10-18 MHz linear probe was used.; Diagnostic test: Transcranial Doppler ultrasonography; During the measurement, Doppler settings were adjusted to detect low flow, and the minor available Doppler gate was used for all TDUS examinations. For TDUS, a temporal window was used approximately 1 cm above the midpoint of the line joining the lateral palpebral fissure and the external auditory meatus. Transcranial Doppler ultrasonography ( TDUS) 3-5 MHz convex array probe was used.; Diagnostic test: Computed Tomography Angiography; Cranial Computed Tomography Angiography

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
ODUS	Orbital artery Doppler ultrasound (ODUS) ODUS measurements: T1; when brain death testing started; T2; 12 hours after the first measurement, T3; before CT angiography, T4; after CT angiography Peak systolic velocity (PSV) cm/s , end-diastolic velocity (EDV) cm/s measurement results. The absence of diastolic flow, reverse diastolic flow (oscillatory flow), and resistive index >1 were considered brain death.	30 minutes
Resistive index (RI)	The resistive index (RI) is a calculated flow parameter in ultrasound, derived from the maximum, minimum, and mean Doppler frequency shifts during a defined cardiac cycle. Along with the pulsatility index (PI), it is typically used to assess the resistance in a pulsatile vascular system.resistive index >1 were considered brain death. RI measurements: T1; when brain death testing started; T2; 12 hours after the first measurement, T3; before CT angiography, T4; after CT angiography . RI = (PSV - EDV) / PSV PSV = peak systolic velocity and EDV = end-diastolic velocity.	30 minutes

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Transcranial Doppler ultrasound (TDUS)	Transcranial Doppler ultrasound (TDUS) ultrasonography involves the use of a low-frequency (≤2 MHz) transducer, placed on the scalp, to insonate the basal cerebral arteries through relatively thin bone windows and to measure the cerebral blood flow velocity (CBFV) normal flow: mean = 55cm/sec. mild: > 120cm/sec. moderate: > 160cm/sec. s	30 minutes
Cerebral blood flow (CTA)	Transcranial Computed Tomography Angiography	40 minutes
Optic nerve diameter	Optic nerve diameter (mm) Orbital artery Doppler was performed simultaneously with ultrasound. The imaging probe position was used transversely and axially and mean values were recorded.	30 minutes

Collaborators and Investigators

• Sponsor: Korgün Ökmen
• Investigators: Principal Investigator: Korgün Ökmen, University of Health Sciences, Bursa Yuksek Ihtisas Training and Research Hospital

Study record dates

Study Major Dates

• Study Start (Actual): January 11, 2017
• Primary Completion (Actual): January 25, 2022
• Study Completion (Actual): June 13, 2022

Study Registration Dates

• First Submitted: January 8, 2024
• First Submitted That Met QC Criteria: January 17, 2024
• First Posted (Actual): January 29, 2024

Study Record Updates

• Last Update Posted (Actual): January 30, 2024
• Last Update Submitted That Met QC Criteria: January 27, 2024
• Last Verified: January 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pathologic Processes; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Neurologic Manifestations; Neurobehavioral Manifestations; Unconsciousness; Consciousness Disorders; Coma; Death; Brain Death
• Other Study ID Numbers: 2017-15 /33

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No