Effect of the Stellate Ganglion Block on the Retinal Microcirculation

November 15, 2025 updated by: Noah Jouett, University of Texas Southwestern Medical Center

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

Surges in the sympathetic nervous system occur at the ictus of a variety of neurological critical illnesses including intracranial hemorrhage and ischemic stroke. It is hypothesized that these exaggerated increases in sympathetic nervous activity produce maladaptations that promote secondary brain injury. One of these possible mechanisms include diffuse vasospasm that cause cerebral ischemia. Hence, methods to abrogate the sympathetic nervous system in this context are under active investigation. One possible method is the regional anesthesia technique of the stellate ganglion nerve block, which is ordinarily used for complex regional pain syndrome, but has been shown to reduce cerebral sympathetic activity and reduces vasospasm in patients with subarachnoid hemorrhage. However, its effect on the microcirculation is not clear. Hence, we propose to study patients receiving the stellate ganglion nerve block as part of their standard medical care and to image their retinal microcirculation before and after the procedure using Optical Coherence Tomography Angiography (OCTA).

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Study Type

Observational

Enrollment (Estimated)

50

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

  • United States
    • Texas
      • Dallas, Texas, United States, 75235
        • Recruiting
        • UT Southwestern Medical Center
        • Contact:
        • Principal Investigator:
          • Noah Jouett, DO, PhD

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Sampling Method

Non-Probability Sample

Study Population

Patients receiving the stellate ganglion block

Description

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

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort
Intervention / Treatment
Intervention Group
Patients receiving the stellate ganglion block
Device: OCTA Scan
Optical Coherence Tomography Angiography before and after receiving the stellate ganglion nerve block.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Vascular and Perfusion Density
Time Frame: One day
Quantitative measure of retinal microperfusion
One day

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

University of Texas Southwestern Medical Center

Investigators

  • Principal Investigator: Noah Jouett, DO, PhD, UT Southwestern Medical Center

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

October 7, 2024

Primary Completion (Estimated)

October 7, 2026

Study Completion (Estimated)

October 7, 2026

Study Registration Dates

First Submitted

December 21, 2024

First Submitted That Met QC Criteria

January 27, 2025

First Posted (Actual)

January 28, 2025

Study Record Updates

Last Update Posted (Actual)

November 19, 2025

Last Update Submitted That Met QC Criteria

November 15, 2025

Last Verified

November 1, 2025

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • STU-2024-1027

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

Pilot study

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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