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Comparison of Anterior Corneal Optical Aberration Induced by CK and Hyperopic LASIK

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ClinicalTrials.gov Identifier: NCT04676620
Recruitment Status : Recruiting
First Posted : December 21, 2020
Last Update Posted : December 21, 2020
Sponsor:
Collaborator:
Tianjin Eye Hospital
Information provided by (Responsible Party):
Wang Hongxia, Shanghai Guanghua Hospital of Integrated Traditional Chinese and Western Medicine

Study Description
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Brief Summary:
Conductive keratoplasty (CK) had shown to be a safe and effective procedure for the treatment of low to moderate hypeopia. It had been approved by the U.S. Food and Drug Administration (FDA) to treat presbyope in early 2004. CK appeals to both surgeons and patients as it avoids the need for flap creation, the use of high intraocular pressure (IOP), or tissue ablation. It utilizes "blended vision" rather than the true monovision used with laser in situ keratomileusis (LASIK), which patients tolerate more readily. There is very little reported research about the induction of wavefront aberration by CK. The symptomatology of high order aberrations (HOA) and the way individual Zernike functions were correlated with visual acuity, contrast sensitivity, visual symptoms. This study measured the HOA created by surgically induced myopic shift via CK and LASIK in an effort to better understand the phenomena of regression, multifocality, pseudo-accommodation and monovision.

Condition or disease Intervention/treatment
Refractive Error Procedure: CK surgery

Detailed Description:
To investigate anterior corneal optical higher order aberration (HOA) induced by conductive keratoplasty (CK) and laser in situ keratomileusis (LASIK). 69 eyes with hyperopia or presbyopia were enrolled. 47 eyes of 47 patients underwent CK procedure, 22 eyes underwent LASIK. Data were acquired preoperatively, and at 3 and 6 months postoperatively. The total Root Mean Square (RMS) of the HOA as well as the individual Zernike polynomials of coma, trefoil, and spherical aberration were analyzed. In CK group, the high order RMS showed significant elevation at 3 months, but it returned to near preoperative levels at 6 months postoperatively. Trefoil (Z33) is the exclusive Zenike pattern to increase significantly following CK, peaking at 3 months and then decreasing back to near preoperative level at 6 months after CK. In the hyperopic LASIK group, coma increased to a peak at 3 month postoperatively, and persisted at sixth month after LASIK. Spherical aberration decreased significantly at 3 months and persisted till the sixth postoperative month. There was significant correlation between ΔSE and Δspherical aberration showed in both groups. The HOA and main Zernike polynomials pattern and their natural changes induced by CK is significantly different from that induced by LASIK in the hyperopic corrected treatment. The amount of achieved hyperopic corrections induced by CK or LASIK is not correlated to the change of HOA patterns such as coma and trefoil, but it is correlated to the change of spherical aberration.
Study Design
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Study Type : Observational
Estimated Enrollment : 69 participants
Observational Model: Cohort
Time Perspective: Prospective
Official Title: Comparison of Anterior Corneal Optical Aberration Induced by Conductive Keratoplasty and Hyperopic Laser in Situ Keratomileusis
Estimated Study Start Date : December 2020
Estimated Primary Completion Date : December 2021
Estimated Study Completion Date : December 2021

Resource links provided by the National Library of Medicine


Groups and Cohorts
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Group/Cohort Intervention/treatment
CK surgery
Conductive keratoplasty (CK) had shown to be a safe and effective procedure for the treatment of low to moderate hypeopia. It had been approved by the U.S. Food and Drug Administration (FDA) to treat presbyope in early 2004. CK appeals to both surgeons and patients as it avoids the need for flap creation, the use of high intraocular pressure (IOP), or tissue ablation.
 Procedure: CK surgery
CK and LASIK are both effective methods for the correction of hypeopia. They have been proved to offer many advantages in terms of visual acuity, corneal sensitivity, and corneal biomechanics compared with traditional refractive surgeries.
LASIK surgery
LASIK surgery is femtosecond laser assisted conventional refractive surgery and has also been proved to offer many advantages in terms of visual acuity, corneal sensitivity, and corneal biomechanics compared with traditional refractive surgeries.
 Procedure: CK surgery
CK and LASIK are both effective methods for the correction of hypeopia. They have been proved to offer many advantages in terms of visual acuity, corneal sensitivity, and corneal biomechanics compared with traditional refractive surgeries.


Outcome Measures
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Primary Outcome Measures :
  1. uncorrected visual acuity [ Time Frame: change from baseline with EDTRS chart at 6 months ]
    uncorrected visual acuity change from baseline at 6 months

  2. best spectacle-corrected visual acuity [ Time Frame: change from baseline with EDTRS chart at 6 months ]
    best spectacle-corrected visual acuity change from baseline with EDTRS chart at 6 months


Secondary Outcome Measures :
  1. near vision [ Time Frame: change from baseline with EDTRS chart at 6 months ]
    near vision change from baseline with EDTRS chart at 6 months

  2. central and peripheral corneal ultrasound pachymetry [ Time Frame: change from baseline with EDTRS chart at 6 months ]
    central and peripheral corneal ultrasound pachymetry change from baseline with EDTRS chart at 6 months


Eligibility Criteria
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Ages Eligible for Study:   40 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population
In this consecutive case series, 69 eyes of 57 patients (30 female and 27 male) with hyperopia or presbyopia were enrolled. Inclusion criteria included age of over 40 years old (yrs), stable refraction, and patients who were planned to induce a myopic shift ranging of -1.00 diopters (D) to -2.50D. Mean patient age was 52.9±5.7 yrs (range from 42 to 68 yrs). The ophthalmic examination for each patient included uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA) (Snellen chart), near vision (Jaeger chart), manifest and cycloplegic refraction, videokeratography, central and peripheral corneal ultrasound pachymetry (thickness), slit-lamp microscopy, dilated fundus examinations, IOP.
Criteria

Inclusion Criteria:

  • age of over 40 years old (yrs)
  • stable refraction
  • planned to induce a myopic shift

Exclusion Criteria:

  • age of less than 40 years old (yrs)
  • significant systemic illnesses
  • congenital myopia,
  • media opacity uveitis
  • glaucoma
  • intraocular surgery refractive surgery
  • neurologic diseases
  • retinal disease
Contacts and Locations
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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): NCT04676620


Contacts
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Contact: Hongxia Wang, director 18302183233 whxeye@163.com
Contact: Qian Fan, professor 15022756478 fanqian2002_yahoo@163.com

Locations
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China, Shanghai
Shanghai Guanghua Integrated Traditional Chinese and Western Medicine Hospital Recruiting
Shanghai, Shanghai, China, 200052
Contact: Hongxia Wang, director    18302183233 ext 18302183233    whxeye@163.com   
Sponsors and Collaborators
Wang Hongxia
Tianjin Eye Hospital
Investigators
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Study Director: Hongxia Wang, director Shanghai Guanghua integrated traditional Chinese and Western Medicine Hospital
More Information
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Publications of Results:

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Responsible Party: Wang Hongxia, Shanghai Guanghua Hospital of Integrated Traditional Chinese and Western Medicine
ClinicalTrials.gov Identifier: NCT04676620    
Other Study ID Numbers: 2020-K-107
First Posted: December 21, 2020    Key Record Dates
Last Update Posted: December 21, 2020
Last Verified: December 2020
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
Keywords provided by Wang Hongxia, Shanghai Guanghua Hospital of Integrated Traditional Chinese and Western Medicine:
conductive keratoplasty
corneal optical aberrations
hyperopic corrections
LASIK
Additional relevant MeSH terms:
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Refractive Errors
Eye Diseases