Measuring retinal blood flow in patients previously infected with COVID-19

Is this trial a fit for you?

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This observational study aims to assess retinal neurovascular coupling and blood flow parameters in individuals who have previously been infected with COVID-19, including those experiencing long COVID-19 symptoms, compared to healthy control subjects. The study utilizes non-invasive techniques such as Dynamic Vessel Analyzer (DVA), Fourier domain optical coherence tomography (FDOCT), and Laser Speckle Flowgraphy (LSFG) to visualize and measure the retinal response to flicker light stimulation. By examining these parameters, researchers hope to uncover potential residual effects of COVID-19 on retinal health and neurovascular function. The findings could provide insights into the neurological and vascular complications associated with COVID-19.

Why it matters

Who can join: the full rules

Inclusion Criteria:

Inclusion criteria for healthy subjects

* Men and women aged over 18 years
* Non-smokers
* Normal findings in the medical history unless the investigator considers an abnormality to be clinically irrelevant
* No previous history of COVID-19 infection
* Negative testing for SARS-CoV-2 seroprevalence using nucleocapsid antibody tests
* Negative PCR test for SARS-CoV-2
* Normal ophthalmic findings, ametropy \< 6 Dpt.

Inclusion criteria for subjects with history of COVID-19 infection

* Men and women aged over 18 years
* Non-smokers
* History of COVID-19 infection (confirmed by a positive PCR test for SARS-CoV2 in the medical history) within the last 6 months
* Positive testing for SARS-CoV-2 seroprevalence using spike protein IgG antibody tests
* Negative PCR test for SARS-CoV-2

Inclusion criteria for subjects with long COVID-19

* Men and women aged over 18 years
* Non-smokers
* History of COVID-19 infection (confirmed by a positive PCR test for SARS-CoV2 in the medical history)
* Positive testing for SARS-CoV-2 seroprevalence
* Negative PCR test for SARS-CoV-2
* Long Covid according to the latest WHO-Guidelines

Exclusion Criteria:

Any of the following will exclude a healthy control subject from the study:

* Symptoms of a clinically relevant illness in the 3 weeks before the first study day
* Presence or history of a severe medical condition as judged by the clinical investigator
* Participation in a clinical trial in the 3 weeks preceding the study
* Blood donation during the previous three weeks
* History or family history of epilepsy
* Presence of any abnormalities preventing reliable measurements in the study eye as judged by the investigator
* Best corrected visual acuity \< 0.8 Snellen
* Pregnancy, planned pregnancy or lactatin
* History of epilepsia

Any of the following will exclude a subject with history of COVID-19 infection from the study:

* Blood donation during the previous three weeks
* History or family history of epilepsy
* Presence of any abnormalities preventing reliable measurements in the study eye as judged by the investigator
* Best corrected visual acuity \< 0.8 Snellen
* Ametropy \>6 Dpt
* Pregnancy, planned pregnancy or lactating
* History of epilepsia

Any of the following will exclude a subject with long COVID-19 from the study:

* Blood donation during the previous three weeks
* History or family history of epilepsy
* Presence of any abnormalities preventing reliable measurements in the study eye as judged by the investigator
* Best corrected visual acuity \< 0.8 Snellen
* Ametropy \>6 Dpt
* Pregnancy, planned pregnancy or lactating
* History of epilepsia
* Diabetes mellitus

Where it's running

• Medical University of Vienna, Department of Clinical Pharmacology
  Vienna, State of Vienna, Austria Recruiting

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How to take part

1. Review the eligibility criteria above with your treating physician.
2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.