- ICH GCP
- US Clinical Trials Registry
- Clinical Trial NCT04684888
Femto-flap Versus SBK Flap,Predictability and Variability
Comparison of Corneal Flap Thickness Using Visumax Femto-Lasik With SubBowman Keratomileusis (SBK) Microkeratome
Study Overview
Status
Conditions
Intervention / Treatment
Detailed Description
Flap creation techniques have evolved from the old manual procedure of mechanical microkeratome to the automated one with the use of microkeratome and more recently to Femto-laser procedure using a variety of machines.
Authors have reported that the primary vision nearly the same despite the different methods of flap creation in the first 6 months post LASER vision correction. Others have reported that a thinner flap is associated with better primary vision and refractive outcomes. SBK (Sub Bowman Keratomileusis), is a procedure in which the Lasik flap is thinner, and has the advantage of leaving a sufficient stromal bed for safer excimer Laser ablation.
There are five types of femtosecond Laser that were already approved currently for Lasik flap creation.
The Zeiss (Visumax FSL ) which has been used in the current study uses 1043 nm, a repetition rate of 500 kHz, and 220-580 femtoseconds pulse duration. Each laser pulse produces micro-photo disruption in the tissue, contiguous few microns sized photo disruptions will create a continuous cut in the corneal tissue at precise preset position and depth.
In the current study, the Visumax flap thickness predictability, accuracy, and variability were compared with the flap created by a single-use Moria SBK microkeratome.
Study Type
Enrollment (Actual)
Phase
- Not Applicable
Contacts and Locations
Study Locations
-
-
-
Baghdad, Iraq, 1001
- Eye Speciality private hospital
-
-
Participation Criteria
Eligibility Criteria
Ages Eligible for Study
Accepts Healthy Volunteers
Genders Eligible for Study
Description
Inclusion Criteria:
- Having refractive errors range from -2 to- 6 DS and from -1 to -3.00DC.
- They have stable refraction for at least one year prior to surgery.
- Normal topography by Placido-Scheimpflug (Sirius, Costruzione Strumenti Oftalmici, Florence, Italia) and normal corneal epithelial map by Anterior segment-OCT system (Optovue Inc, Fremont, California, USA)
Exclusion Criteria:
- Patient with suspicious topography and or corneal epithelial map.
- Patient with corneal pachymetry below 500µm.
- Patients who have a history of previous ocular surgery or trauma.
- Patient with a current or previous history of herpes simplex or herpes zoster.
- Patient with severe dry eye, diabetes, thyrotoxicosis, and connective tissue diseases.
- Patient with Combined ocular diseases like retinal dystrophy or glaucoma.
- Patient with a history of contact lenses use was meant to stop the use of soft contact lenses for at least 2 weeks or hard type for at least 4 weeks before topography and other investigations were done.
Patient who refrains from the required follow-up visits; have been excluded from the study.
-
Study Plan
How is the study designed?
Design Details
- Primary Purpose: Treatment
- Allocation: Non-Randomized
- Interventional Model: Parallel Assignment
- Masking: Double
Arms and Interventions
Participant Group / Arm |
Intervention / Treatment |
---|---|
Active Comparator: Visumax Femto-flap
Fifty eyes of fifty patients with age range 20-38 years, with myopic astigmatism refractive errors, ranged from -2 to- 6 DS and from -1 to -3.00DC, with stable refraction for at least one year before the surgery, normal corneal topography, anterior and posterior segments examinations.
Refractive surgery was planned for both eyes and they chose the Visumax Femto-LASIK after a complete explanation of all the possible complications, costs, and differences.
The right eye of each patient was taken for analysis, LASIK flap thickness was measured six months after the procedures using the anterior segment OCT, at seven points (one central and 3 points at each side of the horizontal meridian).
The three nasal points were located (1mm, 2mm, 3mm respectively) from the center, and the remaining three temporal points located again ( 1mm, 2mm, 3mm) from the center.
|
Under topical anesthesia [Tetracaine eye drop 0.5%]. A-90 µm thick flap was done by using Visumax femtosecond laser. The flap hinge was set to be nasally placed. A nasal-hinge flap with 90 µm thickness, 8.8 mm flap diameter, and 90º side cut angles were created with 500 kHz Visumax FSL, 160 nJ energy [Carl Zeiss, Meditec, Germany]. The sphero- cylindrical refractive corrections with optical zone 6.5 mm and ablation zone 8.0 mm were done by excimer laser operating system [Carl Zeiss, Meditec, MEL 90, Germany]. Automatic iris registration and pupil-tracking system were activated before photoablation. The patient's eyes were examined postoperatively on a slit-lamp biomicroscope and all treatments that were given for home use have been explained in terms of frequency of instillation, possible side effects, and benefits before discharging them on the same day. Follow up visits were scheduled clearly on printed patients' discharging cards. |
Active Comparator: Sub Bowman's keratomileusis (SBK )-Flap group
Fifty eyes of fifty patients with age range 20-38 years, with myopic astigmatism refractive errors, ranged from -2 to- 6 DS and from -1 to -3.00DC, with stable refraction for at least one year before the surgery, normal corneal topography, anterior and posterior segments examinations.
They chose LASIK with mechanical SBK microkeratome surgical approach to be their refractive surgery for both eyes after all the possible complications, costs and differences had been explained clearly.
The right eye of each patient was taken for analysis, LASIK flap thickness was measured six months after the procedures using the anterior segment OCT, at seven points (one central and 3 points at each side of the horizontal meridian).
The three nasal points were located (1mm, 2mm, 3mm respectively) from the center, and the remaining three temporal points located again ( 1mm, 2mm, 3mm) from the center.
|
Under topical anesthesia [Tetracaine eye drop 0.5%] .A-90µm flaps done using Maria one use plus SBK mechanical microkeratome with a nasal located hinge. The sphero- cylindrical refractive corrections with optical zone 6.5 mm and ablation zone 8.0 mm were done by excimer laser operating system [Carl Zeiss, Meditec, MEL 90, Germany]. Automatic iris registration and pupil-tracking system were activated before photoablation. The patient's eyes were examined postoperatively on a slit-lamp biomicroscope and all treatments that were given for home use have been explained in terms of the frequency of instillation, possible side effects, and benefits before discharging them on the same day. Follow up visits were scheduled clearly on printed patients' discharging cards . |
What is the study measuring?
Primary Outcome Measures
Outcome Measure |
Measure Description |
Time Frame |
---|---|---|
Right eye corneal flap thickness was measured by optical coherence tomography(OCT).
Time Frame: 6-months postoperatively
|
The lasik flap thickness in the right eye in both groups were measured six months after the procedures using non touch method by anterior segment OCT without instillation of topical anaesthesia, at seven points in each eye (one central and 3 points at each sides of horizontal meridian).The three nasal points were located (1mm, 2mm, 3mm respectively) from the center and remaining three temporal points located again ( 1mm, 2mm, 3mm) from the center.
Data from both groups were comparing to evaluate predictability and variability of the flap thickness.
|
6-months postoperatively
|
Collaborators and Investigators
Sponsor
Investigators
- Study Director: Suzan Rattan, lecturer, Al-Kindy College of Medicine
Publications and helpful links
Study record dates
Study Major Dates
Study Start (Actual)
Primary Completion (Actual)
Study Completion (Actual)
Study Registration Dates
First Submitted
First Submitted That Met QC Criteria
First Posted (Actual)
Study Record Updates
Last Update Posted (Actual)
Last Update Submitted That Met QC Criteria
Last Verified
More Information
Terms related to this study
Additional Relevant MeSH Terms
Other Study ID Numbers
- 10 Al-KindyCM
Drug and device information, study documents
Studies a U.S. FDA-regulated drug product
Studies a U.S. FDA-regulated device product
This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.
Clinical Trials on Refractive Errors
-
London School of Hygiene and Tropical MedicineBritish Council for Prevention of Blindness; Tanzanian Society for the BlindCompletedUnder- and Uncorrected Significant Refractive ErrorsTanzania
-
Johnson & Johnson Vision Care, Inc.TerminatedRefractive Error CorrectionUnited States
-
Alcon ResearchCompletedRefractive ErrorsUnited States
-
Alcon ResearchCompletedRefractive ErrorsUnited States
-
Alcon ResearchCompletedRefractive ErrorsUnited States
-
Ohio State UniversityNational Eye Institute (NEI); University of HoustonCompleted
-
Coopervision, Inc.Completed
-
Vision Service PlanForesight Regulatory Strategies, Inc.CompletedRefractive ErrorsUnited States
Clinical Trials on Visumax Femto-flap
-
Milton S. Hershey Medical CenterCompletedCataract | AstigmatismUnited States
-
United States Naval Medical Center, San DiegoCarl Zeiss Meditec, Inc.RecruitingAstigmatism | MyopiaUnited States
-
Edward E. MancheCompleted
-
Ziemer Ophthalmic Systems AGRecruiting
-
59th Medical WingNot yet recruiting
-
Odense University HospitalAarhus University HospitalCompleted
-
Dar Al Shifa HospitalCompletedLasik in Myopia
-
The S.N. Fyodorov Eye Microsurgery State InstitutionCompletedCorneal Opacity | Keratoconus
-
Carl Zeiss Meditec, Inc.CompletedAstigmatism | MyopiaUnited States
-
St Vincent's University Hospital, IrelandPelvExCompletedRectal Cancer | Pelvic Cancer | Flap Necrosis | Flap Disorder | Perioperative Complication | Flap IschemiaIreland