MedPath

The Effect Of High And Low Molecular Weight Sodium Hyaluronic Acid Eye Drops After Crosslinking

Completed
Conditions
Keratoconus
Interventions
Device: in vivo Corneal Confocal Microscopy
Diagnostic Test: Corneal Sensitivity
Device: Non invasive tear break up time
Diagnostic Test: Ocular Surface Disease Index Qestionnaire
Device: Corneal tomography
Registration Number
NCT06243991
Lead Sponsor
Marmara University
Brief Summary

Purpose: The objective of this investigation was to assess the impact of eye drops containing high molecular weight hyaluronic acid (HMW-HA) and low molecular weight hyaluronic acid (LMW-HA) on corneal nerve regeneration, dendritic cell (DC) density, corneal sensitivity (CS), and ocular surface parameters in patients with keratoconus following corneal crosslinking (CXL).

Methods: Sixty-three eyes of 55 keratoconus patients were randomized to instill eye drops containing HMW-HA (n: 20) for 12 months, LMW-HA (n:23) for 12 months and polyvinyl alcohol (n: 20) until the epithelial defect closure in the control group after CXL. Subbasal nerve plexsus (SNP) was imaged with corneal confocal microscopy (CCM) and ACCMetrics program was used to quantify corneal nerve fiber density (CNFD), corneal nerve fiber length (CNFL), corneal nerve fiber branching density (CNBD) and corneal nerve fiber total branching density (CTBD). DC density was calculated with Image J software. CS was measured using the Cochet-Bonnet esthesiometer. Ocular Surface Disease Index (OSDI) questionnaire, non-invasive break-up time (NI-TBUT) were evaluated. All measurements were performed before CXL and postoperatively after 1, 3, 6 and 12 months.

Detailed Description

This study assessed individuals aged 18 and above diagnosed with keratoconus and scheduled for epithelium-off CXL. A total of 63 eyes from 55 keratoconus patients were randomly assigned using computer-generated randomization (www.random.org/integers) into three groups: 20 eyes in the HMW-HA group, 23 eyes in the LMW-HA group, and 20 eyes in the control group without the administration of artificial tears.

Post-CXL, the HMW-HA group received topical HMW-HA (Comfort Shield®, i.com medical GmbH, Munich, Germany) three times daily for 12 months, the LMW-HA group received topical LMW-HA (Thealose Duo®, Thea, Clermont-Ferrand, France) three times daily for 12 months, and the control group received topical polyvinyl alcohol (Refresh, Allergan, Dublin, Ireland) three times daily until epithelial defect closure. All participants underwent accelerated epithelium-off CXL (A-CXL) for 10 minutes with 9 mW/cm² ultraviolet-A irradiation. The postoperative standard treatment regimen included topical moxifloxacin (0.5% Vigamox, Alcon Inc, USA) for one week, topical dexamethasone (0.1% Dexasine-SE, Kaysersberg Pharmaceuticals, France) for one week after epithelial closure, followed by topical loteprednol 0.5% (Lotemax, Bausch \& Lomb, USA) for three weeks.

Uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), and manifest spherical equivalent (SE) were recorded at all visits. The assessment was carried out in the following order: Ocular Surface Disease Index (OSDI) questionnaire, noninvasive tear break-up time (NIBUT), corneal tomography (Pentacam, OCULUS, Wetzlar, Germany), corneal sensitivity, corneal fluorescein staining, and CCM imaging. Examinations were conducted preoperatively and at the postoperative 1th, 3rd, 6th and 12th months.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
63
Inclusion Criteria
  • Keratoconus patiens aged 18 and above who had been scheduled for corneal crosslinking
Exclusion Criteria
  • Dry eye disease, corneal thickness below 400 micrometer, pregnancy, breastfeeding, topical or systemic drug use, eye disease other than keratoconus, systemic diseases, active atopy or allergy, contact lens use, ocular surgery history.

Study & Design

Study Type
OBSERVATIONAL
Study Design
Not specified
Arm && Interventions
GroupInterventionDescription
LMW-HA groupOcular Surface Disease Index QestionnaireTwenty-two patiens (23 eyes) received topical LMW-HA (Thealose Duo®, Thea, Clermont-Ferrand, France) three times daily for 12 months.
HMW-HA groupOcular Surface Disease Index QestionnaireSeventeen patiens (20 eyes) received topical HMW-HA (Comfort Shield®, i.com medical GmbH, Munich, Germany) three times daily for 12 months.
Control groupNon invasive tear break up timeNineteen patiens (20 eyes) received topical polyvinyl alcohol (Refresh, Allergan, Dublin, Ireland) three times daily until epithelial defect closure after CXL in control group.
Control groupOcular Surface Disease Index QestionnaireNineteen patiens (20 eyes) received topical polyvinyl alcohol (Refresh, Allergan, Dublin, Ireland) three times daily until epithelial defect closure after CXL in control group.
Control groupCorneal tomographyNineteen patiens (20 eyes) received topical polyvinyl alcohol (Refresh, Allergan, Dublin, Ireland) three times daily until epithelial defect closure after CXL in control group.
LMW-HA groupin vivo Corneal Confocal MicroscopyTwenty-two patiens (23 eyes) received topical LMW-HA (Thealose Duo®, Thea, Clermont-Ferrand, France) three times daily for 12 months.
LMW-HA groupCorneal SensitivityTwenty-two patiens (23 eyes) received topical LMW-HA (Thealose Duo®, Thea, Clermont-Ferrand, France) three times daily for 12 months.
HMW-HA groupCorneal tomographySeventeen patiens (20 eyes) received topical HMW-HA (Comfort Shield®, i.com medical GmbH, Munich, Germany) three times daily for 12 months.
HMW-HA groupCorneal SensitivitySeventeen patiens (20 eyes) received topical HMW-HA (Comfort Shield®, i.com medical GmbH, Munich, Germany) three times daily for 12 months.
HMW-HA groupNon invasive tear break up timeSeventeen patiens (20 eyes) received topical HMW-HA (Comfort Shield®, i.com medical GmbH, Munich, Germany) three times daily for 12 months.
Control groupin vivo Corneal Confocal MicroscopyNineteen patiens (20 eyes) received topical polyvinyl alcohol (Refresh, Allergan, Dublin, Ireland) three times daily until epithelial defect closure after CXL in control group.
Control groupCorneal SensitivityNineteen patiens (20 eyes) received topical polyvinyl alcohol (Refresh, Allergan, Dublin, Ireland) three times daily until epithelial defect closure after CXL in control group.
LMW-HA groupNon invasive tear break up timeTwenty-two patiens (23 eyes) received topical LMW-HA (Thealose Duo®, Thea, Clermont-Ferrand, France) three times daily for 12 months.
HMW-HA groupin vivo Corneal Confocal MicroscopySeventeen patiens (20 eyes) received topical HMW-HA (Comfort Shield®, i.com medical GmbH, Munich, Germany) three times daily for 12 months.
LMW-HA groupCorneal tomographyTwenty-two patiens (23 eyes) received topical LMW-HA (Thealose Duo®, Thea, Clermont-Ferrand, France) three times daily for 12 months.
Primary Outcome Measures
NameTimeMethod
Corneal nerve fiber density (CNFD)Postoperative 1st, 3rd, 6th and 12th months

Automated tracing of nerve fibers program - CCMetrics (CCMetrics; M. A. Dabbah, ISBE, University of Manchester, Manchester, UK) was used to analyze CNFD.

Corneal nerve fiber total branching density (CTBD)Postoperative 1st, 3rd, 6th and 12th months

Automated tracing of nerve fibers program - CCMetrics (CCMetrics; M. A. Dabbah, ISBE, University of Manchester, Manchester, UK) was used to analyze CTBD.

Corneal nerve branch density (CNBD)Postoperative 1st, 3rd, 6th and 12th months

Automated tracing of nerve fibers program - CCMetrics (CCMetrics; M. A. Dabbah, ISBE, University of Manchester, Manchester, UK) was used to analyze CNBD.

Corneal nerve fiber length (CNFL)Postoperative 1st, 3rd, 6th and 12th months

Automated tracing of nerve fibers program - CCMetrics (CCMetrics; M. A. Dabbah, ISBE, University of Manchester, Manchester, UK) was used to analyze CNFL

Corneal SensitivityPostoperative 1st, 3rd, 6th and 12th months

Corneal sensitivity was assessed using a Cochet-Bonnet esthesiometer (Luneau Ophtalmologue, Chartes, France).

Ocular surface disease Index (OSDI) questionnairePostoperative 1st, 3rd, 6th and 12th months

The Turkish validated version of the OSDI, a questionnaire assesing the clinical symptoms of the ocular surface disease, was used. The 4th and 5th questions in the first section, which inquire about blurred vision and reduced vision symptoms, were excluded from the questionnaire as they could already be present in patients with keratoconus disease.

Dendritic cell densityPostoperative 1st, 3rd, 6th and 12th months

The Density of dendritic cells was calculated using ImageJ software (Image V.1.31; National Institutes of Health)

Non invaziv tear break-up time (NI-TBUT)Postoperative 1st, 3rd, 6th and 12th months

The tear break-up time (TBUT) was evaluated non-invasively using a Sirius Scheimpflug camera (CSO, Florence, Italy).

Secondary Outcome Measures
NameTimeMethod
Visual FunctionsBaseline

Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA) by the Snellen chart, based on the logMAR scoring system and manifest spherical equivalent (SE) were assessed.

Refractive OutcomesPostoperative 1st, 3rd and 6th months

Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA) by the Snellen chart, based on the logMAR scoring system and manifest spherical equivalent (SE) were assessed.

Keratometric FindingsPostoperative 1st, 3rd and 6th months

Corneal tomography (Pentacam, OCULUS, Wetzlar Germany) was used to obtain the data for K1, K2, Kmean, Kmax, and the Thinnest point (TP).

Trial Locations

Locations (1)

Marmara University

🇹🇷

Istanbul, Pendik, Turkey

© Copyright 2025. All Rights Reserved by MedPath