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Simultaneous Corneal Wavefront-Guided Trans-PRK and Corneal Collagen Crosslinking After ICRS Implantation for Moderate Keratoconus

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ClinicalTrials.gov Identifier: NCT03355430
Recruitment Status : Completed
First Posted : November 28, 2017
Last Update Posted : November 28, 2017
Sponsor:
Information provided by (Responsible Party):
Yonsei University

Brief Summary:
The investigators aim to investigate the effects of combined corneal wavefront-guided transepithelial photorefractive keratectomy (tPRK) and accelerated corneal collagen cross-linking (CXL) after intracorneal ring segment (ICRS) implantation in patients with moderate keratoconus. Medical records of 23 eyes of 23 patients undergoing combined tPRK and CXL after ICRS implantation were retrospectively analyzed. Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction spherical equivalent (MRSE), corneal indices based on Scheimpflug tomography, higher-order aberrations (HOAs), and corneal biomechanical properties were evaluated before and after ICRS implantation, and at 1, 3, and 6 months after combined tPRK and CXL. Corneal biomechanical properties were measured using the dynamic Scheimpflug analyzer at approximately the same time of day.

Condition or disease Intervention/treatment
Moderate Keratoconus Procedure: combined corneal wavefront-guided transepithelial photorefractive keratectomy (tPRK) Procedure: accelerated corneal collagen cross-linking (CXL)

Detailed Description:
The investigators aim to investigate the effects of combined corneal wavefront-guided transepithelial photorefractive keratectomy (tPRK) and accelerated corneal collagen cross-linking (CXL) after intracorneal ring segment (ICRS) implantation in patients with moderate keratoconus. Medical records of 23 eyes of 23 patients undergoing combined tPRK and CXL after ICRS implantation were retrospectively analyzed. Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction spherical equivalent (MRSE), corneal indices based on Scheimpflug tomography, higher-order aberrations (HOAs), and corneal biomechanical properties were evaluated before and after ICRS implantation, and at 1, 3, and 6 months after combined tPRK and CXL. Corneal biomechanical properties were measured using the dynamic Scheimpflug analyzer at approximately the same time of day. The dynamic Scheimpflug analyzer automatically calculated corneal deformation amplitude, radius values, and maximal concave power when the cornea is deformed to its greatest curvature by the air puff. The deformation amplitude is defined as the maximum amplitude when the cornea is deformed to its greatest concave curvature and is influenced by corneal stiffness. The radius values represent the central concave curvature at the highest concavity (depressed to the highest concavity), while maximal concave power is the inverse radius of the curvature at the highest concavity.

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Study Type : Observational
Actual Enrollment : 23 participants
Observational Model: Case-Only
Time Perspective: Retrospective
Official Title: Simultaneous Corneal Wavefront-Guided Trans-PRK and Corneal Collagen Crosslinking After ICRS Implantation for Moderate Keratoconus
Actual Study Start Date : July 7, 2016
Actual Primary Completion Date : January 2, 2017
Actual Study Completion Date : January 2, 2017

Resource links provided by the National Library of Medicine

Drug Information available for: Collagen

Group/Cohort Intervention/treatment
moderate keratoconus group
moderate keratoconus group underwent combined corneal wavefront-guided transepithelial photorefractive keratectomy (tPRK) and accelerated corneal collagen cross-linking (CXL) after intracorneal ring segment (ICRS) implantation
Procedure: combined corneal wavefront-guided transepithelial photorefractive keratectomy (tPRK)
After at least 1 month (average 2.7 ± 1.1 months; range 1 to 4 months), all patients were scheduled for combined corneal wavefront-guided tPRK and accelerated CXL treatment. tPRK between the corneal ring segments was performed using an excimer laser (Amaris 1050 Excimer Laser platform; Schwind eye-tech-solutions GmbH and Co KG, Kleinostheim, Germany).

Procedure: accelerated corneal collagen cross-linking (CXL)
After at least 1 month (average 2.7 ± 1.1 months; range 1 to 4 months), all patients were scheduled for combined corneal wavefront-guided tPRK and accelerated CXL treatment. tPRK between the corneal ring segments was performed using an excimer laser (Amaris 1050 Excimer Laser platform; Schwind eye-tech-solutions GmbH and Co KG, Kleinostheim, Germany).




Primary Outcome Measures :
  1. visual acuity [ Time Frame: Pre-operation (baseline) ]
    visual acuity in eyes undergoing combined corneal wavefront-guided transepithelial photorefractive keratectomy and accelerated corneal collagen cross-linking after intracorneal ring segment implantation in patients with moderate keratoconus

  2. visual acuity [ Time Frame: 1 minute before tPRK-CXL(transepithelial photorefractive keratectomy-accelerated corneal collagen cross-linking) ]
    visual acuity in eyes undergoing combined corneal wavefront-guided transepithelial photorefractive keratectomy and accelerated corneal collagen cross-linking after intracorneal ring segment implantation in patients with moderate keratoconus

  3. visual acuity [ Time Frame: 1 month after tPRK-CXL ]
    visual acuity in eyes undergoing combined corneal wavefront-guided transepithelial photorefractive keratectomy and accelerated corneal collagen cross-linking after intracorneal ring segment implantation in patients with moderate keratoconus

  4. visual acuity [ Time Frame: 3-month after tPRK-CXL ]
    visual acuity in eyes undergoing combined corneal wavefront-guided transepithelial photorefractive keratectomy and accelerated corneal collagen cross-linking after intracorneal ring segment implantation in patients with moderate keratoconus

  5. visual acuity [ Time Frame: 6-month after tPRK-CXL ]
    visual acuity in eyes undergoing combined corneal wavefront-guided transepithelial photorefractive keratectomy and accelerated corneal collagen cross-linking after intracorneal ring segment implantation in patients with moderate keratoconus


Secondary Outcome Measures :
  1. Corneal indices [ Time Frame: Pre-operation (baseline) ]
    Multiple corneal indices were measured at the 8-mm zone using the Scheimpflug tomography system (Pentacam HR; OCULUS).

  2. Corneal indices [ Time Frame: 1 minute before tPRK-CXL ]
    Multiple corneal indices were measured at the 8-mm zone using the Scheimpflug tomography system (Pentacam HR; OCULUS).

  3. Corneal indices [ Time Frame: 1 month after tPRK-CXL ]
    Multiple corneal indices were measured at the 8-mm zone using the Scheimpflug tomography system (Pentacam HR; OCULUS).

  4. Corneal indices [ Time Frame: 3-month after tPRK-CXL ]
    Multiple corneal indices were measured at the 8-mm zone using the Scheimpflug tomography system (Pentacam HR; OCULUS).

  5. Corneal indices [ Time Frame: 6-month after tPRK-CXL ]
    Multiple corneal indices were measured at the 8-mm zone using the Scheimpflug tomography system (Pentacam HR; OCULUS).



Information from the National Library of Medicine

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Ages Eligible for Study:   20 Years to 45 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population
Patient was intolerant to contact lenses, had moderate keratoconus without apical scarring, and if progression had been noted over the previous 6 months. All included patients underwent combined corneal wavefront-guided tPRK and CXL at least 1 month (average 2.7 ± 1.1 months; range 1 to 4 months) after ICRS implantation. We excluded patients with central or para-central corneal scarring, central pachymetry < 400 microns, corneal endothelial cell density of less than 2000 cells/mm2, systemic autoimmune disease, a history of herpetic corneal disease, pregnancy, lactation, or severe dry eye syndrome.
Criteria

Inclusion Criteria:

  • intolerant to contact lenses
  • moderate keratoconus without apical scarring
  • if progression had been noted over the previous 6 months
  • All included patients underwent combined corneal wavefront-guided tPRK and CXL at least 1 month (average 2.7 ± 1.1 months; range 1 to 4 months) after ICRS implantation.

Exclusion Criteria:

  • central or para-central corneal scarring
  • central pachymetry < 400 microns
  • corneal endothelial cell density of less than 2000 cells/mm2
  • systemic autoimmune disease
  • a history of herpetic corneal disease
  • pregnancy
  • lactation
  • severe dry eye syndrome

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03355430


Locations
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Korea, Republic of
Department of Ophthalmology, Yonsei University College of Medicine
Seoul, Korea, Republic of, 03722
Sponsors and Collaborators
Yonsei University
Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
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Responsible Party: Yonsei University
ClinicalTrials.gov Identifier: NCT03355430    
Other Study ID Numbers: 4-2016-0403
First Posted: November 28, 2017    Key Record Dates
Last Update Posted: November 28, 2017
Last Verified: November 2017
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No

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Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Additional relevant MeSH terms:
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Keratoconus
Corneal Diseases
Eye Diseases