To investigate the effect of eye-tracker system on ablation zone centration after femtosecond-assisted laser in situ keratomileusis (FS-LASIK) in myopic patients.
Design
Randomised, contralateral, parallel group trial with blinded outcome assessment on 70 biletral myopic patients. Randomisation was done with balanced block pattern in block size of 2 on the right of each patients.
Settings and conduct
In this trial, 70 myopic patients aged 20 to 45 years with myopia ≥ 3.0 D, who are candidates for femtosecond-assisted laser in situ keratomileusis (FS-LASIK) enroll in Noor Eye Hospital. Ophthalmic examination and pentacam imaging will be performed at baseline and 3 months after surgery. Topographic centration of the treatment zone is defined as offset from corneal vertex in X-coordinate, Y-coordinate, and vector distance and compare between two groups after adjusting the correlation between two eyes. The effect of decentration on change in vision, refraction and postoperative higher order abberations (HOA) will be assessed.
Participants/Inclusion and exclusion criteria
Patients with:
- age 20 to 45 years of both gender
- myopia≥ 3.0 D
- stable refraction in the past year (change ± 0.50 D or less)
- RSB of at least 300.0 µm
- without ectasia sign
Intervention groups
Patients with bilateral myopia will be entered the study. One eye of each patient is allocated in the eye-tracker group and the other eye is placed in the control group (without using eye-tracker).
Main outcome variables
-Decentration in X-coordinate and Y-coordinate
- Vectorial distance from corneal vertex
- Study groups
-Vision, refraction, and aberrations
General information
Reason for update
Acronym
IRCT registration information
IRCT registration number:IRCT20100706004333N4
Registration date:2021-11-22, 1400/09/01
Registration timing:registered_while_recruiting
Last update:2021-11-22, 1400/09/01
Update count:0
Registration date
2021-11-22, 1400/09/01
Registrant information
Name
Soheila Asgari
Name of organization / entity
Noor eye hospital
Country
Iran (Islamic Republic of)
Phone
+98 21 8865 1515
Email address
sasgari@noorvision.com
Recruitment status
Recruitment complete
Funding source
Expected recruitment start date
2021-11-22, 1400/09/01
Expected recruitment end date
2022-02-19, 1400/11/30
Actual recruitment start date
empty
Actual recruitment end date
empty
Trial completion date
empty
Scientific title
Effect of eye-tracker system in FS-LASIK on optical zone centration: a contralateral randomized clinical trial
Public title
Comparison of manual and automatic laser ablation in feto-LASIK
Purpose
Treatment
Inclusion/Exclusion criteria
Inclusion criteria:
myopia≥ 3.0D
stable refraction in the past year (change ± 0.50 D or less)
residual stromal bed thickness (RSB) of at least 300.0 µm
Exclusion criteria:
Corneal ectasia
Age
From 20 years old to 45 years old
Gender
Both
Phase
N/A
Groups that have been masked
Participant
Care provider
Outcome assessor
Data analyser
Sample size
Target sample size:
70
Randomization (investigator's opinion)
Randomized
Randomization description
In this contralateral clinical trial, two eyes of each patients randomly allocated in each study group by balanced block randomization (BBR) to achieve a best power in the analysis. BBR is used in a block size of 2 on the right eye of each patient. With this method, sequencing of eye-tracker and manual cods of right eye is detremined by a table of randome number and binary blocks. In this way, one eye of each patient will be allocated in the eye-tracker group and the other eye in the control group (without using eye-tracker). To concealment, randomization is performed by a non-surgeon. The technician was informed about the allocated group of each eyes at the time of surgery. The surgeon will be masked to the groups until to surgery time.
Blinding (investigator's opinion)
Double blinded
Blinding description
The patints are masekd to the groups until the end of study. The surgeon is masked to each eye patient group until surgery. Also statistician and ophthalmic healthcare providers are masked to the treatment allocation of each eye.
Placebo
Not used
Assignment
Parallel
Other design features
Secondary Ids
empty
Ethics committees
1
Ethics committee
Name of ethics committee
Research Ethics Committees of School of Medicine- Tehran University of Medical Sciences
Street address
Faculty of medicine, Poursina Ave., Qods Ave., Enqelab Ave.
City
Tehran
Province
Tehran
Postal code
1417653761
Approval date
2021-10-27, 1400/08/05
Ethics committee reference number
IR.TUMS.MEDICINE.REC.1400.820
Health conditions studied
1
Description of health condition studied
Myopia
ICD-10 code
H52.13
ICD-10 code description
Myopia, bilateral
Primary outcomes
1
Description
Decentration of ablation zone from corneal vertex
Timepoint
3 months after surgery
Method of measurement
Pachymetric map by Pentacam
Secondary outcomes
1
Description
visual acuity
Timepoint
3 months after surgery
Method of measurement
Snellen chart
2
Description
Refraction
Timepoint
3 months after surgery
Method of measurement
Retinoscope
3
Description
corneal aberrations
Timepoint
3 months after surgery
Method of measurement
Pentacam
Intervention groups
1
Description
In femtosecond assisted laser in situ keratomileusis (FS-LASIK), after topical anesthesia, the flap (110.0 µm thick) is created by Femto LDV (Ziemer Ophthalmic Systems AG, Port, Switzerland). After flap lift, wavefront-optimized ablation is performed using AMARIS 1050RS (SCHWIND, Munich, Germany). The optical zone is 6.5 mm for moderate myopia, 6.0 mm for high myopia, and blend zone was 1.25 mm for all cases. Based on the random groups of each eye, the eye-tracker is turned on (with eye-tracker) and off (without eye-tracker) by the device engineer during ablation. Postoperative treatment regimen includes chloramphenicol eye drop 0.5% (Sina Darou, Tehran, Iran) every 6 hours to 3 days and betamethasone 0.1% eye drops (Sina Darou, Tehran, Iran) every 6 hours to 7 days.
Category
Treatment - Surgery
2
Description
In femtosecond assisted laser in situ keratomileusis (FS-LASIK), after topical anesthesia, the flap (110.0 µm thick) is created by Femto LDV (Ziemer Ophthalmic Systems AG, Port, Switzerland). After flap lift, wavefront-optimized ablation is performed using AMARIS 1050RS (SCHWIND, Munich, Germany). The optical zone is 6.5 mm for moderate myopia, 6.0 mm for high myopia, and blend zone was 1.25 mm for all cases. Based on the random groups of each eye, the eye-tracker is turned on (with eye-tracker) and off (without eye-tracker) by the device engineer during ablation. Postoperative treatment regimen includes chloramphenicol eye drop 0.5% (Sina Darou, Tehran, Iran) every 6 hours to 3 days and betamethasone 0.1% eye drops (Sina Darou, Tehran, Iran) every 6 hours to 7 days.
Category
Treatment - Surgery
Recruitment centers
1
Recruitment center
Name of recruitment center
Noor Eye Hospital
Full name of responsible person
Hassan Hashemi, MD
Street address
#96, Esfandiar Blvd., VAli asr Ave.
City
Tehran
Province
Tehran
Postal code
1968653111
Phone
+98 21 82400
Email
research@norc.ac.ir
Sponsors / Funding sources
1
Sponsor
Name of organization / entity
Noor Eye Hospital
Full name of responsible person
Hassan Hashemi
Street address
#96, Esfandiar Blvd., Vliasr Ave.
City
Tehran
Province
Tehran
Postal code
1968653111
Phone
+98 21 82400
Email
research@norc.ac.ir
Grant name
Grant code / Reference number
Is the source of funding the same sponsor organization/entity?
Yes
Title of funding source
Noor Eye Hospital
Proportion provided by this source
100
Public or private sector
Private
Domestic or foreign origin
Domestic
Category of foreign source of funding
empty
Country of origin
Type of organization providing the funding
Other
Person responsible for general inquiries
Contact
Name of organization / entity
Noor Eye Hospital
Full name of responsible person
Soheila Asgari
Position
Research assistant
Latest degree
Ph.D.
Other areas of specialty/work
Epidemiology
Street address
#96, Esfandiar Blvd., Valiasr Ave.
City
Tehran
Province
Tehran
Postal code
1968653111
Phone
+98 21 8240 1624
Fax
Email
soheilaasgari@gmail.com
Person responsible for scientific inquiries
Contact
Name of organization / entity
Noor Eye Hospital
Full name of responsible person
Soheila Asgari
Position
Research assistant
Latest degree
Ph.D.
Other areas of specialty/work
Epidemiology
Street address
#96, Esfandiar Blvd., Valiasr Ave.
City
Tehran
Province
Tehran
Postal code
1968653111
Phone
0098 82401624
Email
soheilaasgari@gmail.com
Person responsible for updating data
Contact
Name of organization / entity
Noor eye hospital
Full name of responsible person
Soheila Asgari
Position
Research assistant
Latest degree
Ph.D.
Other areas of specialty/work
Epidemiology
Street address
#96 Esfandiar Blvd., Vali’asr Ave.
City
Tehran
Province
Tehran
Postal code
1968653111
Phone
+98 21 8865 1515
Fax
+98 21 8865 1514
Email
soheilaasgari@gmail.com
Sharing plan
Deidentified Individual Participant Data Set (IPD)
Yes - There is a plan to make this available
Study Protocol
Yes - There is a plan to make this available
Statistical Analysis Plan
Yes - There is a plan to make this available
Informed Consent Form
Yes - There is a plan to make this available
Clinical Study Report
Yes - There is a plan to make this available
Analytic Code
Not applicable
Data Dictionary
Not applicable
Title and more details about the data/document
The anonymous data will be available in case of reasonable request by corresponding author.
When the data will become available and for how long
6 months after publication
To whom data/document is available
A member of a scientific board
Under which criteria data/document could be used
For clinical or research utilization
From where data/document is obtainable
Sending an email to the corresponding author / Hassan Hashemi (research@norc.ac.ir)
Sending an email to the co-author / Soheila Asgari (soheilaasgari@gmail.com)
What processes are involved for a request to access data/document
Sending name and affiliation through an academic email