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Completed

NCT Number: NCT03291873

Topography-Guided Customized PRK Versus Q-value Adjusted PRK in Correction of Myopia With or Without Astigmatism

This study will include patients who will undergo PRK in both eyes, for each patient each eye will be randomly allocated to one of 2 procedures:

topography-guided ablation in one eye (group I) and Q-factor customized ablation in the other eye (group II).

Alcon/Wavelight Light Laser Technolo¬gie (GmbH, Erlangen, Germany) will be used for photoablation.

The wavelight Topolyzer (Wavelight AG, Erlan¬gen, Germany)and CSO Sirius scheimpflug camera combined with Placido corneal topography (CSO, Florence,Italy) will be used before and 1, 3 and 6 months after PRK. Refrac¬tive visual outcomes and corneal aberration changes will be compared between the two treatment modalities.

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Key information

Conditions

Myopia Eye Diseases Refractive Errors

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Eyecare centre, Maadi, Cairo Governorate, Egypt

Loading trial locations.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Age more than 18 years
  • Myopia with up to -6.5 D with or without astigmatism up to -4.75 D

Exclusion criteria

  • anterior segment abnormalities (ie, cataracts, corneal scarring)
  • basement membrane disease
  • history of recurrent corneal erosions
  • Schirmer's test less than 5 mm
  • established or forme fruste keratoconus
  • macular or retinal disease
  • current use of immunosuppressive therapy
  • autoimmune disease
  • pregnancy, and lactation

Treatment and study plan

PRK

Procedure

PRK using Alcon-Wavelight Excimer Laser EX 500

Primary outcomes

  1. change in Postoperative spherical equivalent depending on manifest refraction after autorefractometer

    Time frame: 1 , 3 and 6 months postoperative

  2. change in visual acuity using snellen chart

    Time frame: 1 , 3 and 6 months postoperative

  3. change in corneal wavefront aberrations

    Time frame: 1 , 3 and 6 months postoperative

    assessed by topolyzer

  4. change in Q value anterior at 6mm RMS, RMS of astigmatism, RMS of coma and RMS of spherical aberrations. Strehl ratio : Qvalue,RMS,strehl ratio by CSO Sirius scheimpflug

    Time frame: 1,3 and 6months

    by CSO Sirius scheimpflug

  5. change in total RMS

    Time frame: 1,3 and 6months

    by CSO Sirius scheimpflug

  6. change in strehl ratio

    Time frame: 1,3 and 6 months

    by CSO scheimpflug

  7. change in Q value

    Time frame: 1,3 and 6 months

    assessed by topolyzer

Secondary outcomes

  1. efficacy:ratio of postoperative decimal UDVA to preoperative decimal CDVA

    Time frame: 6 months

    ratio of postoperative decimal UDVA to preoperative decimal CDVA

  2. contrast sensitivity

    Time frame: 6 months

    cambridge low contrast sensitivity

  3. predictability

    Time frame: 6 months

    eyes within 1.0 D of emmetropia

  4. safety:ratio of mean preoperative decimal CDVA to mean postoperative decimal CDVA

    Time frame: 6 months

    ratio of mean preoperative decimal CDVA to mean postoperative decimal CDVA

  5. stability

    Time frame: 6 months

    change of more than 0.5D over

Sponsors and collaborators

Lead sponsor

Kasr El Aini Hospital

Other

Registry information

Official study title

Topography-Guided Customized PRK (Photorefractive Keratectomy) Versus Q-value Adjusted PRK in Correction of Myopia With or Without Astigmatism

Important dates

Study start
2017
Primary completion
2019
Study completion
2019
First posted
Sep 25, 2017
Registry last updated
Jul 7, 2020

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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