Pupil Centroid Shift Compensation in Photorefractive Keratectomy Candidates

Sponsor

Shahid Beheshti University of Medical Sciences (Other)

Overall Status

Unknown status

CT.gov ID

NCT03844178

Collaborator

(none)

104

Enrollment

Location

Arms

4.6

Anticipated Duration (Months)

22.5

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

patients who are candidates of PRK will be recruited in this intrasubject randomized clinical trial. Inclusion criteria are myopia or myopic astigmatism with refractive cylinder. Exclusion criteria were unstable refractive error, age less than 21 years old, corneal opacity, keratoconus, keratoconus suspects, residual corneal stromal thickness less than 350 µm, moderate or severe dry eye disease and any other ocular pathology other than refractive error. Complete eye exam will be performed preoperatively including: uncorrected distance visual acuity (UDVA), best spectacle corrected distance visual acuity (CDVA), cyclorefraction, slit lamp biomicroscopy, Goldmann applannation tonometry, dual scheimpflug tomography (Ziemmer), topography in mesopic condition accompanied by pupilometry and iris registration (Topolyzer Vario, Alcon Laboratories, Inc., Fort Worth, TX), and funduscopy with dilated pupil.

Surgical Technique The same surgeon (A.F.) will perform all surgeries. After installation of Tetracaine 1%, periorbital skin will be prepared with povidone iodine 5%. Iris registration will be performed in all eyes before epithelial removal. Ethylalcohol 20.0% into a 9.0 mm well for 20 seconds will be applied on the central cornea, and then the epithelium of the central 9.0 mm area will be removed by hockey knife. In the right eye of each patient PCS compensation will be turned on (PCS-On group) and in the left eye it will be turned off (PCS-Off group). Excimer laser ablation will be performed by Wavelight Allegretto EX500 (Alcon, Fort Worth, TX, USA). Selection of which eye to be first ablated will be done randomly. Randomization will be performed based on a computer software by a Biostatistician which produced the first eye to be operated. Static cyclotorsion compensation will be active in all eyes. The ablation profile will be wavefront-optimized in all cases.

Postoperative Course Postoperatively, chloramphenicol 0.5% eye drops and betamethasone 0.1% eye drops will be prescribed every 6 hours for 10 days. Thereafter, Fluorometholone 0.1% eye drops every 6 hours for 1 month and every 8 hours for the next month will be given. Follow-up examinations were scheduled at 1, 2, 3, 4, 7 and 15 days and 1, 2, 3, and 6 months postoperatively. After contact lens removal each follow-up examination includes the UDVA, manifest refraction, and IOP measurements as well as a slit lamp biomicroscopy. Corneal imaging with Galilei tomography, CDVA and cyclorefraction will be performed at the final follow-up examination 6 months postoperatively.

Condition or Disease	Intervention/Treatment	Phase
Pupil Centroid Shift	Procedure: The option for compensation of Pupil centroid shift was ON Procedure: The option for compensation of Pupil centroid shift was OFF Drug: installation of Tetracaine 1% Procedure: Photorefractive keratectomy (PRK)	Phase 2

Study Design

Study Type:

Interventional

Anticipated Enrollment :

104 participants

Allocation:

Randomized

Intervention Model:

Single Group Assignment

Masking:

Single (Participant)

Primary Purpose:

Treatment

Official Title:

Role of Pupil Centroid Shift Compensation on Lower and Higher Order Aberrations During Photorefractive Keratectomy: An Eye-to-Eye Study

Anticipated Study Start Date :

Feb 10, 2019

Anticipated Primary Completion Date :

Jun 1, 2019

Anticipated Study Completion Date :

Jul 1, 2019

Arms and Interventions

Arm	Intervention/Treatment
Active Comparator: The right eyes with compensation for Pupil centroid shift	Procedure: The option for compensation of Pupil centroid shift was ON The option for compensation of Pupil centroid shift was ON Drug: installation of Tetracaine 1% installation of Tetracaine 1% Procedure: Photorefractive keratectomy (PRK) periorbital skin will be prepared with povidone iodine 5%. Iris registration will be performed in all eyes before epithelial removal. Ethylalcohol 20.0% into a 9.0 mm well for 20 seconds will be applied on the central cornea, and then the epithelium of the central 9.0 mm area will be removed by hockey knife. Excimer laser ablation will be performed by Wavelight Allegretto EX500 (Alcon, Fort Worth, TX, USA)
Active Comparator: The left eyes without compensation for Pupil centroid shift	Procedure: The option for compensation of Pupil centroid shift was OFF The option for compensation of Pupil centroid shift was OFF Drug: installation of Tetracaine 1% installation of Tetracaine 1% Procedure: Photorefractive keratectomy (PRK) periorbital skin will be prepared with povidone iodine 5%. Iris registration will be performed in all eyes before epithelial removal. Ethylalcohol 20.0% into a 9.0 mm well for 20 seconds will be applied on the central cornea, and then the epithelium of the central 9.0 mm area will be removed by hockey knife. Excimer laser ablation will be performed by Wavelight Allegretto EX500 (Alcon, Fort Worth, TX, USA)

Arm

Intervention/Treatment

Active Comparator: The right eyes with compensation for Pupil centroid shift

Procedure: The option for compensation of Pupil centroid shift was ON

The option for compensation of Pupil centroid shift was ON

Drug: installation of Tetracaine 1%

installation of Tetracaine 1%

Procedure: Photorefractive keratectomy (PRK)

periorbital skin will be prepared with povidone iodine 5%. Iris registration will be performed in all eyes before epithelial removal. Ethylalcohol 20.0% into a 9.0 mm well for 20 seconds will be applied on the central cornea, and then the epithelium of the central 9.0 mm area will be removed by hockey knife. Excimer laser ablation will be performed by Wavelight Allegretto EX500 (Alcon, Fort Worth, TX, USA)

Active Comparator: The left eyes without compensation for Pupil centroid shift

Procedure: The option for compensation of Pupil centroid shift was OFF

The option for compensation of Pupil centroid shift was OFF

Drug: installation of Tetracaine 1%

installation of Tetracaine 1%

Procedure: Photorefractive keratectomy (PRK)

Outcome Measures

Primary Outcome Measures

Postoperative refractive error [2 months]
Snellen chart and subjective refraction

Secondary Outcome Measures

Root Mean Square (RMS) of higher order aberration [6 months]
wavefront analysis by galilei scan

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years to 40 Years

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Inclusion Criteria:

myopia
myopic astigmatism

Exclusion Criteria:

unstable refractive error, age less than 21 years old
corneal opacity
keratoconus, keratoconus suspects
residual corneal stromal thickness less than 350 µm
moderate or severe dry eye disease
any other ocular pathology other than refractive error

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Ophthalmic Research Center	Tehran		Iran, Islamic Republic of

Sponsors and Collaborators

Shahid Beheshti University of Medical Sciences

Investigators

None specified.

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.

Responsible Party:

Zahra Rabbani Khah, Head of ophthalmic research center, Shahid Beheshti University of Medical Sciences

ClinicalTrials.gov Identifier:

NCT03844178

Other Study ID Numbers:

97362

First Posted:

Feb 18, 2019

Last Update Posted:

Feb 18, 2019

Last Verified:

Feb 1, 2019

Studies a U.S. FDA-regulated Drug Product:

Studies a U.S. FDA-regulated Device Product:

Additional relevant MeSH terms:

Tetracaine

Study Results

No Results Posted as of Feb 18, 2019