Contribution of Posterior Corneal Astigmatism to Total Corneal Astigmatism in a Sample of Egyptian Population

NCT04393740 | Unknown FDA Device

• 1 other identifier: Ms-184-2019
• Study Type: observational
• Target: 356
• Locations: 1 country
• Sites: 1

Brief Summary

The magnitude of posterior corneal astigmatism was considered negligible due to the smaller difference in the refractive index between the cornea and the aqueous . though ,neglecting the posterior corneal astigmatism lead to errors during calculation of the toric iols (over or under estimation ) . so we aim to determine the percentage of contribution of posterior corneal astigmatism to total corneal astigmatism in a sample of Egyptian population using scheimpflug imaging (Pentacam ).

Conditions

Corneal Astigmatism

Outcome Measures

Primary Outcomes (1)

• contribution of posterior corneal astigmatism to magnitude of total corneal astigmatism

  to detect the contribution of posterior corneal astigmatism to total corneal astigmatism to avoid errors during calculation of toric Intra ocular lenses

  3 months

Interventions

scheimpflug imaging using pentacam DIAGNOSTIC_TEST

corneal tomography imaging using pentacam device (based on Scheimpflug principle )

Eligibility Criteria

• Age: 18 Years - 45 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)
• Sampling Method: Non-Probability Sample

Study Population

candidates presenting for refractive surgery .

You may qualify if:

• Patients with corneal astigmatism(±0.5D up tp ±4 D )
• Age (18-45 years )
• Refractive error (myopia up to -8D)
• Hyperopia up to +4
• Patients who have clear cornea .
• Good quality Scheimpflug analyzer scans.

You may not qualify if:

• Patients who have any corneal opacity .
• Patients who underwent any Previous corneal surgery .
• Patients who have Co existing corneal pathology.
• Glaucomatus patients.
• Patients with any Concomitant ocular disease .
• Patients with History of previous ocular trauma .

Sponsors & Collaborators

• Cairo University: lead

Study Sites (1)

kasr El Aini medical school

Cairo, Egypt

RECRUITING

Related Publications (2)

• Ferreira TB, Ribeiro P, Ribeiro FJ, O'Neill JG. Comparison of Methodologies Using Estimated or Measured Values of Total Corneal Astigmatism for Toric Intraocular Lens Power Calculation. J Refract Surg. 2017 Dec 1;33(12):794-800. doi: 10.3928/1081597X-20171004-03.

  PMID: 29227506 BACKGROUND

• Rydstrom E, Westin O, Koskela T, Behndig A. Posterior corneal astigmatism in refractive lens exchange surgery. Acta Ophthalmol. 2016 May;94(3):295-300. doi: 10.1111/aos.12965. Epub 2016 Jan 30.

  PMID: 26825986 BACKGROUND

MeSH Terms

Conditions

Astigmatism

Condition Hierarchy (Ancestors)

Refractive Errors; Eye Diseases

Central Study Contacts

alaa mo badawy, Msc

CONTACT

01008858267; alaabadawy93@gmail.com

sarah A azzam, MD

CONTACT

01227425601; Sarahazzam@ymail.com

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: CROSS SECTIONAL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Resident of ophthalmology kasr el AINI

Study Record Dates

• First Submitted: May 14, 2020
• First Posted: May 19, 2020
• Study Start: April 15, 2020
• Primary Completion: July 15, 2020
• Study Completion: August 15, 2020
• Last Updated: May 19, 2020

Record last verified: 2020-05

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL
• Time Frame: the data would be available within 3 months and would be available for 6 months

Locations

EG (1)