Retrospective Observational Study of Posterior Keratometry Measured

NCT04422080 | Completed

• 1 other identifier: RECHMPL20_0338
• Study Type: observational
• Target: 200
• Locations: 1 country
• Sites: 1

Brief Summary

Keratoconus is a progressive bilateral disease leading to an apical stromal thinning and an irregular astigmatism by a steepening of the cornea, causing visual impairment. The causes are not yet well known, but it seems to be linked to several comorbidities. Keratoconus is a rare and for a long-time asymptomatic condition and its diagnosis needs meticulous screening for the early stages. Detecting it as soon as possible is a goal as it could lead to earlier avoiding of contributing factors such as eye rubbing and earlier treatment if needed. The gold standard for keratoconus screening and staging is computerized videotography. It gives information about anterior and posterior corneal bulging, steepening, and thinning. It can be completed by anterior segment optical coherence tomography, which can show corneal scarring. Since recently, some biometry devices can give some information about the posterior corneal keratometry trough swept source optical coherence tomography measures. The measurement of the total corneal power instead of an extrapolation lead to better precision in refractive results after cataract surgery in some cases. It also helped to increase our knowledge about posterior corneal astigmatism. In normal eyes, average posterior corneal astigmatism is 0.37 diopters and against the rule in 91 percent of eyes. There is a correlation between the magnitude of anterior and posterior astigmatism. In keratoconus eyes, several studies have shown that there is an alignment between axes of the anterior and posterior corneal astigmatism. These studies have been performed on computerized videotopography devices. The goal of this study was to confirm or deny previous observations about posterior astigmatism in keratoconus eyes, and to assess if the rotation of axis between anterior and posterior astigmatism measured by IOL Master 700® can be a good sign for detection of early stages and fruste keratoconus.

Conditions

Keratoconus

Keywords

Ophthalmology; Keratoconus

Outcome Measures

Primary Outcomes (1)

• Posterior keratometry

  Posterior cylinder and axis measured on biometry

  1 day

Secondary Outcomes (1)

• Total keratometry

  1 day

Study Arms (2)

Keratoconus patient

Patient with keratoconus disease diagnosed on videotopography

Healthy patient

Patient consulting for keratoconus screening with no keratoconus on videotopography

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

included all patients having a specialized cornea consultation, in which keratoconus was diagnosed or suspected from November 2018 to May 2020 in the department of Ophthalmology, University Hospital Gui de Chauliac in Montpellier (France),

You may qualify if:

• \- Keratoconus diagnosed on videotopography

You may not qualify if:

• \- loss of sight due to another condition than keratoconus, corneal scarring leading to lack or mistaken data, corneal graft, non-keratoconus related corneal ectasia such as post Laser in Situ Keratomileusis (LASIK) ectasia or keratoglobus

Sponsors & Collaborators

• University Hospital, Montpellier: lead

Study Sites (1)

UH Montpellier

Montpellier, 34295, France

Location

MeSH Terms

Conditions

Keratoconus

Condition Hierarchy (Ancestors)

Corneal Diseases; Eye Diseases

Study Officials

• Arnaud : MUYL CIPOLLINA, Internship of ophthalmology

  University Hospitals of Montpellier

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: RETROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: June 4, 2020
• First Posted: June 9, 2020
• Study Start: November 1, 2019
• Primary Completion: June 1, 2020
• Study Completion: June 3, 2020
• Last Updated: June 9, 2020

Record last verified: 2020-06

Locations

FR (1)