| CTRI Number |
CTRI/2017/03/008075 [Registered on: 14/03/2017] Trial Registered Prospectively |
| Last Modified On: |
08/03/2017 |
| Post Graduate Thesis |
No |
| Type of Trial |
Interventional |
|
Type of Study
|
Medical Device |
| Study Design |
Randomized, Parallel Group Trial |
|
Public Title of Study
|
Comparative study of topography of corneal layers for refractive surgery planning |
|
Scientific Title of Study
|
Customization of laser ablation profiles using Bowman’s layer topography |
| Trial Acronym |
|
|
Secondary IDs if Any
|
| Secondary ID |
Identifier |
| NIL |
NIL |
|
|
Details of Principal Investigator or overall Trial Coordinator (multi-center study)
|
| Name |
Dr Rohit Shetty |
| Designation |
|
| Affiliation |
Narayana Nethralaya |
| Address |
Division of cornea and refractive services, 2nd floor, 121C Chord Road, Rajajinagar,
Bangalore, Karnataka
Bangalore
KARNATAKA
560010
India |
| Phone |
9611102568 |
| Fax |
8023377329 |
| Email |
drrohitshetty@yahoo.com |
|
Details of Contact Person
Scientific Query
|
| Name |
Dr Rohit Shetty |
| Designation |
|
| Affiliation |
Narayana Nethralaya |
| Address |
Division of cornea and refractive services, 2nd floor,121C Chord Road, Rajajinagar,
Bangalore, Karnataka
Bangalore
KARNATAKA
560010
India |
| Phone |
9611102568 |
| Fax |
8023377329 |
| Email |
drrohitshetty@yahoo.com |
|
Details of Contact Person
Public Query
|
| Name |
Dr Rohit Shetty |
| Designation |
|
| Affiliation |
Narayana Nethralaya |
| Address |
Division of cornea and refractive services, 2nd floor,121C Chord Road, Rajajinagar,
Bangalore, Karnataka
Bangalore
KARNATAKA
560010
India |
| Phone |
9611102568 |
| Fax |
8023377329 |
| Email |
drrohitshetty@yahoo.com |
|
|
Source of Monetary or Material Support
|
| Narayana Nethralaya,
121C Chord Road, Rajajinagar,
bangalore-560010, Karnataka |
|
|
Primary Sponsor
|
| Name |
Narayana Nethralaya |
| Address |
121C Chord Road, Rajajinagar,
Bangalore, Karnataka |
| Type of Sponsor |
Other [Hospital and Nonprofit research institute] |
|
|
Details of Secondary Sponsor
|
| Name |
Address |
| Alcon Laboratories Pvt Ltd |
3rd floor, Crescent 4, Prestige Shantiniketan, Whitefield, Bangalore 560048, Karnataka |
|
|
Countries of Recruitment
|
India |
|
Sites of Study
|
| No of Sites = 1 |
| Name of Principal
Investigator |
Name of Site |
Site Address |
Phone/Fax/Email |
| Rohit Shetty |
Narayana nethralaya |
Division of cornea and refractive services, 2nd floor, 121C Chord Road, Rajajinagar,
Bangalore 560010, Karnataka
Bangalore
KARNATAKA |
9611102568
8023377329
drrohitshetty@yahoo.com |
|
|
Details of Ethics Committee
|
| No of Ethics Committees= 1 |
| Name of Committee |
Approval Status |
| Narayana Nethralaya Ethics Committee |
Approved |
|
|
Regulatory Clearance Status from DCGI
|
|
|
Health Condition / Problems Studied
|
| Health Type |
Condition |
| Patients |
Patients willing to undergo refractive surgery to correct myopia and astigmatsim, |
|
|
Intervention / Comparator Agent
|
| Type |
Name |
Details |
| Comparator Agent |
Bowmans layer topography coupled with CONTURA topography guided laser-assisted in situ keratomileusis |
Fellow eye of the same patient will be treated with CONTURA laser-assisted in situ keratomileusis system using Bowmanslayer topography |
| Intervention |
CONTURA laser-assisted in situ keratomileusis treatment |
One eye will undergo laser-assisted in situ keratomileusis with CONTURA Topography guided system |
|
|
Inclusion Criteria
|
| Age From |
18.00 Year(s) |
| Age To |
50.00 Year(s) |
| Gender |
Both |
| Details |
1. Patients should be between 18 to 50 years of age.
2. Patient must have stable myopia for a minimum period of one year (a change of 0.25D or less) as documented by prior clinical records or current spectacle correction.
Patient must have a corrected distance visual acuity of 0.8 Decimal or better,
3. Patient must have a spherical equivalent refraction less than -10D
4. Patient must have refractive astigmatism less than -3D.
|
|
| ExclusionCriteria |
| Details |
1. Patient must not have a central corneal thickness less than 480 micrometer
2.Patient must not have a calculated residual s stromal bed thickness of less than 250 micrometer after the surgery
3. Patient must not have symptoms or signs of keratoconus, diabetes, collagen vascular disease, pregnancy, breastfeeding and any prior ocular surgery.
4. Patient must not have an inter-ocular difference of more than 1.00 diopter of spherical or 0.50 D of cylindrical refractive error.
5. Patient must not be on chronic systemic steroids or other medication that can affect wound healing.
6. Patient must not be allergic to primary or alternative medications.
7. Patient must not be using rigid contact lenses for the last three weeks or soft contact lenses for at least 1 week before the preoperative evaluation.
|
|
|
Method of Generating Random Sequence
|
Computer generated randomization |
|
Method of Concealment
|
On-site computer system |
|
Blinding/Masking
|
Open Label |
|
Primary Outcome
|
| Outcome |
TimePoints |
| Visual acuity corrected and uncorrected, wavefront aberrations |
Pre-surgery, 1 week, 1 month, 3 month, 6 month |
|
|
Secondary Outcome
|
| Outcome |
TimePoints |
| Corneal tomography and biomechanical response |
Pre-surgery, 1 week, 1 month, 3 month, 6 month |
|
|
Target Sample Size
|
Total Sample Size="80"
Sample Size from India="80"
Final Enrollment numbers achieved (Total)= "Applicable only for Completed/Terminated trials"
Final Enrollment numbers achieved (India)="Applicable only for Completed/Terminated trials" |
|
Phase of Trial
|
Phase 4 |
|
Date of First Enrollment (India)
|
01/04/2017 |
| Date of Study Completion (India) |
Applicable only for Completed/Terminated trials |
| Date of First Enrollment (Global) |
Date Missing |
| Date of Study Completion (Global) |
Applicable only for Completed/Terminated trials |
|
Estimated Duration of Trial
|
Years="2"
Months="0"
Days="2" |
|
Recruitment Status of Trial (Global)
|
Not Applicable |
| Recruitment Status of Trial (India) |
Not Yet Recruiting |
|
Publication Details
|
None |
|
Individual Participant Data (IPD) Sharing Statement
|
Will individual participant data (IPD) be shared publicly (including data dictionaries)?
|
|
Brief Summary
|
For years, conventional refractive treatment has
been based on refractive error of the patient. Ablation of the tissue is
planned assuming topography of the anterior surface of the cornea, which is
actually the air-epithelium interface. However, the treatment is actually
delivered to the stroma. It is generally assumed that the topography of the
Bowman’s layer is the same as the topography of the anterior surface of the
cornea. However, new evidence suggests that this may not be the case in normal
corneas [1]. In keratoconic corneas as well, topography of the anterior surface
of the cornea can be different from the topography of the Bowman’s layer [2].
Therefore, our hypothesis is that planning of ablation pattern can benefit from
the topography of the Bowman’s layer. This can lead to potentially better
refractive and aberration outcomes. To achieve this, we have developed novel
image processing methods, where optical coherence tomography scans of the
cornea can be used to reconstruct the topography of the anterior surface as
well as the Bowman’s layer. Our method is fully non-invasive and can be
performed pre-operatively unlike past studies [1, 2]. Figure 1 shows an example
of a normal eye with Pentacam topography (left), OCT topography of the anterior
surface (middle) and OCT topography of the Bowman’s layer (right). Note the
distinct change in pattern of astigmatism from inferior to regular astigmatism.
Thus surgical planning based on Bowman’ layer topography will be different from
the topography of the anterior surface.
References:
1.
Salah-Mabed
I, Saad A, Gatinel D. Topography of the corneal epithelium and Bowman layer in
low to moderately myopic eyes. J Cataract Refract Surg. 2016; 42(8): 1190-7.
2.
Touboul
D, Trichet E, Binder PS, Praud D, Seguy C, Colin J. Comparison of front-surface
corneal topography and Bowman membrane specular topography in keratoconus. J
Cataract Refract Surg. 2012; 38(6): 1043-9.
3.
Jain
AK, Malhotra C, Pasari A, Kumar P, Moshirfar M. Outcomes of topography-guided
versus wavefront-optimized laser in situ keratomileusis for myopia in virgin
eyes. J Cataract Refract Surg. 2016; 42(9): 1302-1311 |