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Corneal Topography Asymmetry Indices Changes After Corneal Refractive Surgery

Corneal Topography Asymmetry Indices Changes After Corneal Refractive Surgery

Status
Completed
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT04589091
Enrollment
30
Registered
2020-10-19
Start date
2021-04-13
Completion date
2022-01-30
Last updated
2022-02-08

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Myopia

Brief summary

To evaluate the changes that occur in the corneal indices after corneal refractive surgery either PRK or LASIK.

Detailed description

Retrospectively review the medical records of all patients who underwent refractive surgery referred from the out-patient clinic of Tanta University hospital between September 2015 and September 2020 . Data collection will include: Preoperative and postoperative Evaluation: Age, sex, uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest and cycloplegic refraction, Slit lamp biomicroscopy, fundus examination. Data of Corneal Tomography keratometric using Scheimpflug camera (Pentacam Oculus- Germany) :that includes the following indices 1. Average keratometric value (K mean) in diopters 2. Maximum simulated keratometry (Kmax) in diopters 3. Index of Surface Variance (ISV) in microns 4. Index of Vertical Asymmetey (IVA) in microns 5. Radii Minimum (R min) in microns 6. Index of height asymmetry (IHA) in microns 7. Index of height decantation (IHD) in microns 8. Aberration coefficient (ABR) The data of the pentacam will be collected pre-operative and analyzed at 1 month, 3 months and 6 months with recording of the complications.

Interventions

OTHERRefractive surgery

Refractive surgery for correction of error of refraction

Sponsors

Tanta University
Lead SponsorOTHER

Study design

Observational model
OTHER
Time perspective
RETROSPECTIVE

Eligibility

Sex/Gender
ALL
Age
19 Years to 35 Years
Healthy volunteers
No

Inclusion criteria

* Patients who underwent refractive surgery either PRK, LASIK with age between 19 and 35 years old

Exclusion criteria

* Kertoconus. * Corneal scarring. * Previous corneal infections. * Minimum corneal thickness at the thinnest location less than 400 µm. * History of uveitis or ocular allergy. * Pre-existing glaucoma. * Data not available

Design outcomes

Primary

MeasureTime frameDescription
To evaluate the changes that occur in the corneal indices after corneal refractive surgery either PRK or LASIK.6 monthsUsing the results of measurements of Scheimpflug camera (Pentacam Oculus- Germany) :that includes the following indices 1. Average keratometric value (K mean) in diopters 2. Maximum simulated keratometry (Kmax) in diopters 3. Index of Surface Variance (ISV) in microns 4. Index of Vertical Asymmetey (IVA) in microns 5. Radii Minimum (R min) in microns 6. Index of height asymmetry (IHA) in microns 7. Index of height decantation (IHD) in microns 8. Aberration coefficient (ABR) The numbers from preoperative records will be compared with postoperative records after the refractive surgery is done . All the values will be expressed as mean ± standard deviation and the data will be analyzed as 1 months, 3 months and 6 months after surgery

Countries

Egypt

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026