The Characteristics of Backscattering With Depth in the Progression of Keratoconus

September 18, 2023 updated by: Tianjin Eye Hospital

The Characteristics of Backscattering With Depth in the Progression of Keratoconus and Its Role in Forme Fruste Keratoconus Detection

To investigate the variation in backscattering with depth between forme fruste keratoconus (FFKC), keratoconus, and normal eyes; to determine the backscattering changes in the characteristics of keratoconus progression; and to explore the diagnostic value of backscattering in FFKC.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Detailed Description

To investigate the variation in backscattering with depth between forme fruste keratoconus (FFKC), keratoconus, and normal eyes; to determine the backscattering changes in the characteristics of keratoconus progression; and to explore the diagnostic value of backscattering in FFKC. A Scheimpflug corneal tomography image and caliper tool were used to obtain backscatter at every 2% depth at the thinnest point of the cornea, with the measured values expressed in grayscale units (GSU).

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Observational

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
223

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • China
    • Tianjin
      • Tianjin, Tianjin, China
        • Tianjin Eye Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

  • Child
  • Adult
  • Older Adult

Accepts Healthy Volunteers

Yes

Sampling Method

Non-Probability Sample

Study Population

The study was performed on patients with keratoconus and healthy participants admitted to Tianjin Eye Hospital from January 2020 to December 2022.

Description

Inclusion Criteria:

  1. BCVA <20/20 and a history of myopia or astigmatism;
  2. presence of any of the following positive signs on slit lamp examination: corneal stromal thinning, cone-shaped anterior protrusions, Fleischer's ring, Vogt's striae, epithelial or subepithelial scarring;
  3. abnormal corneal topography (maximum keratometry (K) value of >47.2 diopters (D), bow-tie pattern with skewed radial axes, or inferior-superior asymmetry(3-mm I-S keratometric difference >1.4 D).

Exclusion Criteria:

1. Patients with severe corneal scarring that affected light scattering and density maps showing "black holes" 2.Participatients with other corneal diseases 3. Eyes that have undergone surgery or trauma 4. Eyes with corneal dystrophy

-

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort

Group / Cohort

A group or subgroup of participants in an observational study that is assessed for biomedical or health outcomes.
forme fruste keratoconus
1) no other eye abnormalities except myopia and astigmatism; 2) transparent cornea; 3) no positive signs of keratoconus on slit lamp examination or morphology examination (excluding the appearance of keratoconus as described above, and simultaneously satisfying A0B0C0D0, Index of Surface variance (ISV) < 30, and Keratoconus Index (KI) < 1.07); and 4) Belin/Ambrósio enhanced ectasia total derivation value(BAD-D)≤1.6
Clinical keratoconus
46.5 D ≤ Mean K <52 D; 55≤ ISV<200; and 1.10 ≤ KI <1.50
severe keratoconus
Mean K ≥ 52D; ISV≥ 200; and KI≥ 1.50
normal eye
one eye of healthy participants before refractive surgery were randomly selected. Comprehensive ophthalmic examinations were performed before surgery, which confirmed that the cornea was clear and normal in shape. For this group, there was no family history of keratoconus, no other diseases except ametropia, and no corneal dilatation one year after surgery.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
backscattering
Time Frame: through study completion, an average of 1 year
Standard measurements were performed using a Pentacam (Pentacam HR; Oculus, Wetzlar, Germany);The average brightness of a predetermined area of the cornea was calculated, shown as densitometry, and recorded in GSU ranging from 0 to 100 (0, cornea is transparent without opacity; 100, cornea is completely opaque).
through study completion, an average of 1 year

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Tianjin Eye Hospital

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
January 1, 2020

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
December 1, 2022

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
December 30, 2022

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
September 8, 2023

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
September 18, 2023

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
September 22, 2023

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
September 22, 2023

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
September 18, 2023

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
September 1, 2023

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • KY-2023020

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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