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

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

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

Study Overview

• Status: Completed
• Conditions: Microbiota; Ocular Surface
• Intervention / Treatment: Diagnostic test: Conjunctival swab; Drug: artificial tears; Drug: Oxybuprocaine Hydrochloride 0.4% Eye Drops

Detailed Description

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.

• Study Type: Interventional
• Enrollment (Actual): 24
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Belgium
  • Leuven, Belgium, 3000
    • University Hospitals Leuven, Department of Ophthalmology

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

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

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Drop of artificial tears; A drop op Thealoz duo	Diagnostic test: Conjunctival swab; Swab of the conjunctival fornices of both eyes; Drug: artificial tears; One drop of artificial tears in the other eye; Other Names: Thealoz duo
Active Comparator: Drop op anesthetic; A drop of oxybuprocaïne	Diagnostic test: Conjunctival swab; Swab of the conjunctival fornices of both eyes; Drug: Oxybuprocaine Hydrochloride 0.4% Eye Drops; One drop of topical anesthesia in one eye; Other Names: anesthetic

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Difference in richness of the microbial flora measured as operational taxonomic units	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.	5 minutes per sampling session
Difference in evenness of distribution of the microbial flora measured as operational taxonomic units	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.	5 minutes per sampling session

Collaborators and Investigators

• Sponsor: Universitaire Ziekenhuizen KU Leuven
• Investigators: Principal Investigator: Heleen Delbeke, MD, Universitaire Ziekenhuizen KU Leuven

Study record dates

Study Major Dates

• Study Start (Actual): August 19, 2019
• Primary Completion (Actual): December 31, 2021
• Study Completion (Actual): December 31, 2021

Study Registration Dates

• First Submitted: December 4, 2019
• First Submitted That Met QC Criteria: December 6, 2019
• First Posted (Actual): December 10, 2019

Study Record Updates

• Last Update Posted (Actual): July 22, 2022
• Last Update Submitted That Met QC Criteria: July 18, 2022
• Last Verified: June 1, 2022

More Information

Terms related to this study

• Keywords: Anesthesia; Ocular surface microbiome; Extraction protocol
• Additional Relevant MeSH Terms: Physiological Effects of Drugs; Central Nervous System Depressants; Peripheral Nervous System Agents; Sensory System Agents; Anesthetics, Local; Pharmaceutical Solutions; Anesthetics; Ophthalmic Solutions; Lubricant Eye Drops; Benoxinate
• Other Study ID Numbers: S62672

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