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

Universitaire Ziekenhuizen KU Leuven

Status: Completed

Conditions: Ocular Surface; Microbiota

Treatments: Drug: artificial tears; Drug: Oxybuprocaine Hydrochloride 0.4% Eye Drops; Diagnostic Test: Conjunctival swab

Study type: Interventional

Funder types: Other

Identifiers

NCT04193774

S62672

Details and patient eligibility

About

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

Full 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.

Enrollment: 24 patients

Sex: All

Ages: 18+ years old

Volunteers: Accepts Healthy Volunteers

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

Trial design

Primary purpose: Diagnostic

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Double Blind

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24 participants in 2 patient groups, including a placebo group

Drop of artificial tears

Placebo Comparator group

Description:

A drop op Thealoz duo

Treatment:

Diagnostic Test: Conjunctival swab

Drug: artificial tears

Drop op anesthetic

Active Comparator group

Description:

A drop of oxybuprocaïne

Treatment:

Diagnostic Test: Conjunctival swab

Drug: Oxybuprocaine Hydrochloride 0.4% Eye Drops