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Completed

NCT Number: NCT04193774

Optimization of Sampling and Processing of Samples for Molecular Microbial Research on Ocular Surface Samples

The use of anesthetics and the processing of the retrieved samples are major confounding factors that influence the results of microbiome research.

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Key information

Conditions

Microbiota Ocular Surface

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

University Hospitals Leuven, Department of Ophthalmology

Leuven, 3000, Belgium

About this study

The use of anesthetics is subject of discussion in ocular surface microbiome research. One publication showed a significant lower alpha diversity when using an anesthetic. However, the diluting effect of the anesthetic drop itself was not accounted for. On the other hand, using anesthetics will enable patients to tolerate sampling better and this might allow better sampling. To analyze the effect of anesthetic drops on the composition of the ocular surface microbiome, we sampled volunteers undergoing general anesthesia. By using artificial tears as a control, we aimed at accounting for the diluting effect of the anesthetic. By using volunteers under general anesthesia, we wanted to assure similar pressure with or without topical anesthesia since the executor was not influenced by the patient's reaction.

Furthermore, the effect of different extraction protocols on sequencing results will be assessed by sampling different volunteers in both eyes on non consecutive days.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Willing to undergo sampling of the conjunctiva
  • Fluent in written and verbal Dutch
  • Capable of giving informed consent

Exclusion criteria

  • Allergy to oxybuprocaine
  • Medication usage in one eye only

Treatment and study plan

Conjunctival swab

Diagnostic Test

Swab of the conjunctival fornices of both eyes

Oxybuprocaine Hydrochloride 0.4% Eye Drops

Drug

One drop of topical anesthesia in one eye

Other names: anesthetic

Artificial Tears

Drug

One drop of artificial tears in the other eye

Other names: Thealoz duo

Primary outcomes

  1. Difference in richness of the microbial flora measured as operational taxonomic units

    Time frame: 5 minutes per sampling session

    The difference in richness and evenness of distribution of the microbial flora of samples retrieved after a drop of topical anesthesia versus samples retrieved after a drop of artificial tears.

  2. Difference in evenness of distribution of the microbial flora measured as operational taxonomic units

    Time frame: 5 minutes per sampling session

    The effect of the different microbial DNA extraction protocols on the richness and evenness of distribution of the microbial flora of the ocular surface will be compared.

Sponsors and collaborators

Lead sponsor

Universitaire Ziekenhuizen KU Leuven

Other

Registry information

Official study title

Optimization of Sampling for Molecular Microbial Research on Ocular Surface Samples and Building a Framework for Comparing Current Sequencing Results Using Different Extraction Protocols.

Acronym: EPSO

Important dates

Study start
2019
Primary completion
2021
Study completion
2021
First posted
Dec 10, 2019
Registry last updated
Jul 22, 2022

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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