Evaluation of the Change in the DA Ratio, IR and SSI as Parameters of Corneal Biomechanics Post Different LVC Procedures

Cairo University (CU)

Status: Completed

Conditions: Corneal Biomechanics

Treatments: Diagnostic Test: CORVIS

Study type: Interventional

Funder types: Other

Identifiers

NCT05377099

MD 187-2020

Details and patient eligibility

About

In the study, The Investigators will compare the participates' corneal biomechanical properties including:

Deformation Amplitude ratio (Da Ratio) Integrated Radius (IR) Stress strain index (SSI)

All measurements will be taken before and after 3 months of LVC.

Full description

Each Participant will undergo preoperative pentacam and corvis scan for his eyes and the 3 months post operative.

The participants are divided into 3 groups, one who underwent LASIK, one PRK and one Femto LASIK.

Collected data will before and after surgery will be compared in each arm and then the 3 arms will be compared together.

Enrollment: 33 patients

Sex: All

Ages: 18 to 40 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• • Age range 18 - 40 years.

  • Normal eyes with normal tomographic indices.
  • Patients with maximum mean refractive spherical equivalent (MRSE) of -7.00 diopters and with maximum astigmatism of -3.00 diopters.

Exclusion criteria

• • Patients with any other coexisting corneal diseases.

  • Keratoconus eyes.
  • Eyes with previous refractive corneal surgery.
  • Patients with increased intraocular pressure.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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33 participants in 3 patient groups

Laser In situ Keratomileusis (LASIK)

Active Comparator group

Description:

Measurement of the deformation amplitude ratio, integrated radius and stress strain index as corneal biomechanical indices in refractive patients before and after LASIK

Treatment:

Diagnostic Test: CORVIS

Femto-second assisted LASIK (FS-LASIK)

Active Comparator group

Description:

Measurement of the deformation amplitude ratio, integrated radius and stress strain index as corneal biomechanical indices in refractive patients before and after Femto LASIK

Treatment:

Diagnostic Test: CORVIS

Photorefractive Keratectomy (PRK)

Active Comparator group

Description:

Measurement of the deformation amplitude ratio, integrated radius and stress strain index as corneal biomechanical indices in refractive patients before and after PRK

Treatment:

Diagnostic Test: CORVIS