Investigating the effects of stellate ganglion block on retinal blood flow

Effect of the Stellate Ganglion Block on the Retinal Microcirculation: A Pilot Study

Observational University of Texas Southwestern Medical Center · NCT06797752

This study is testing if a special nerve block used for pain relief can improve blood flow in the eyes of patients with severe brain injuries.

Quick facts

Study typeObservational
Enrollment50 (estimated)
Ages18 Years and up
SexAll
SponsorUniversity of Texas Southwestern Medical Center Academic / other
Locations1 site (Dallas, Texas)
Trial IDNCT06797752 on ClinicalTrials.gov

What this trial studies

This observational study examines the impact of stellate ganglion nerve blocks on retinal microcirculation in patients with severe brain injuries, such as subarachnoid and intracerebral hemorrhages. The study aims to understand how this regional anesthesia technique, typically used for pain management, may influence cerebral sympathetic activity and potentially reduce vasospasm. Patients receiving the nerve block as part of their standard care will undergo OCTA scans to assess changes in their retinal microcirculation. The findings could provide insights into the broader implications of sympathetic nervous system modulation in critical neurological conditions.

Who should consider this trial

Good fit: Ideal candidates include adults aged 18 and older who are receiving stellate ganglion nerve blocks for approved indications.

Not a fit: Patients who are pregnant, non-English speaking, or have physical limitations preventing them from participating in the OCTA imaging will not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to improved management strategies for patients with severe brain injuries by mitigating secondary brain damage.

How similar studies have performed: While the use of stellate ganglion blocks has shown promise in reducing sympathetic activity, this specific application in retinal microcirculation is novel and has not been extensively tested.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Age 18 years or older
* Patients receiving the stellate ganglion nerve block for an approved indication, e.g. complex regional pain syndrome

Exclusion Criteria:

* Pregnancy
* Non-English speaking
* Temporary or permanent physical limitation that renders the patient unable to sit up and look inside OCTA device

Where this trial is running

Dallas, Texas

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions OCTASevere Brain InjurySubarachnoid HemorrhageIntracerebral Hemorrhage
Last reviewed 2026-06-10 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.