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Limbal Relaxing Incisions Versus Paired 4 mm Clear Corneal Incisions on Steep Meridian During Phacoemulsification (LRI-CCI)

Primary Purpose

Corneal Astigmatism

Status
Not yet recruiting
Phase
Not Applicable
Locations
Study Type
Interventional
Intervention
surgical correction of astigmatism with cataract
Sponsored by
Sohag University
About
Eligibility
Locations
Arms
Outcomes
Full info

About this trial

This is an interventional treatment trial for Corneal Astigmatism focused on measuring astigmatism, limbal relaxing incisions, cataract surgery

Eligibility Criteria

21 Years - 80 Years (Adult, Older Adult)All SexesDoes not accept healthy volunteers

Inclusion Criteria:

  • Cataract patients aged 21- 80 years.
  • keratometric astigmatism 1D - 4D.
  • Healthy clear cornea

Exclusion Criteria:

  • History of previous keratorefractive or anterior segment surgery.
  • Previous ocular trauma .
  • Corneal scar or opacities.
  • Irregular corneal astigmatism.
  • Cataract unsuitable for phacoemulsification.
  • Ongoing chronic ocular pathology

Sites / Locations

    Arms of the Study

    Arm 1

    Arm 2

    Arm Type

    Experimental

    Experimental

    Arm Label

    Clear corneal incisions

    Limbal relaxing incision

    Arm Description

    the Steep meridian will be identified and marked, One clear corneal incision will be made on one side of the steep axis using 2.4mm keratome knife then enlarged to 4mm after completion of cataract surgery & other corneal 4mm incision is added to the other side of the steep axis

    Single or paired LRI will be performed on the steep axis prior to phaco-emulsification procedure using a 600 μm diamond guarded blade.

    Outcomes

    Primary Outcome Measures

    change of corneal astigmatism assessed by K readings measurment
    keratometry readings by autokeratometry, Topcon KR-8900, Tokyo, Japan ) confirmed by Pentacam (Sirius Scheimpflug Placido topography .CSO, Florence, Italy).

    Secondary Outcome Measures

    change of manifest refraction assessed by autorefractometer (Topcon KR-8900, Tokyo,
    sphere & cylinder power in diopters combined to report spherical equivalent measured by autorefractometer (Topcon KR-8900, Tokyo, Japan )

    Full Information

    First Posted
    October 17, 2022
    Last Updated
    October 20, 2022
    Sponsor
    Sohag University
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    1. Study Identification

    Unique Protocol Identification Number
    NCT05593263
    Brief Title
    Limbal Relaxing Incisions Versus Paired 4 mm Clear Corneal Incisions on Steep Meridian During Phacoemulsification
    Acronym
    LRI-CCI
    Official Title
    Assistant Lecturer of Ophthalmology Department, Sohag University
    Study Type
    Interventional

    2. Study Status

    Record Verification Date
    October 2022
    Overall Recruitment Status
    Not yet recruiting
    Study Start Date
    November 15, 2022 (Anticipated)
    Primary Completion Date
    November 15, 2023 (Anticipated)
    Study Completion Date
    February 15, 2024 (Anticipated)

    3. Sponsor/Collaborators

    Responsible Party, by Official Title
    Principal Investigator
    Name of the Sponsor
    Sohag University

    4. Oversight

    Studies a U.S. FDA-regulated Drug Product
    No
    Studies a U.S. FDA-regulated Device Product
    No
    Data Monitoring Committee
    No

    5. Study Description

    Brief Summary
    The goal of this is prospective, computer based randomized clinical trial is to compare the efficacy of reduction of the pre-existing corneal astigmatism at the time of cataract surgery in patients admitted in sohag university hospital. the main questions it aims to answer are : Is limbal relaxing incisions as effective as the paired opposite 4mm clear corneal incisions technique in reduction of corneal astigmatism at the time of cataract surgery ? Are both techniques effective in treating mild degrees of corneal Astigmatism ? All participants will have full ophthalmological examination necessary for routine cataract surgery, then randomly divided into 2 groups, clear corneal incision group & limbal relaxing incision group. Researcher will compare difference between both groups regarding the following : Uncorrected distance visual acuity (UCVA) Best Corrected visual acuity (BCVA) keratometry readings
    Detailed Description
    This is prospective clinical trial will be established in Sohag university hospital. All cataract patients who will be admitted and meet the study inclusion criteria will be enrolled in this study. Candidates will be computer based randomly divided into two groups, opposite clear corneal incisions group & limbal relaxing incision group. Inclusion criteria: Cataract patients aged 21- 80 years. keratometric astigmatism 1Diopter - 4 Diopters. Healthy clear cornea. Exclusion criteria: History of previous keratorefractive or anterior segment surgery. Previous ocular trauma . Corneal scar or opacities. Irregular corneal astigmatism. Cataract unsuitable for phacoemulsification. Ongoing chronic ocular pathology Withdrawal criteria: Suturing the wounds. Placement of more than 2 side ports. Any complication necessitating enlargement of the main incision. Wound infections. Second procedures within the follow-up period. intraocular lens tilt or in sulcus implantation. Number of patients with adverse events, missed follow ups or changing plans will be registered and mentioned separately . Preoperative evaluation: Full ophthalmological examination will be done for all patients and include: Uncorrected distance visual acuity (UCVA) Best Corrected visual acuity (BCVA) Slit lamp biomicroscopy Refraction Intraocular pressure measurement by (Goldman Applanation Tonometry) Fundus examination. keratometry (autokeratometry, Topcon KR-8900, Tokyo, Japan ) Pentacam (Sirius Scheimpflug Placido topography .CSO, Florence, Italy). Evaluation of corneal aberrations( by IOLMaster 700 and the KR-1W Aberrometer (Topcon) Data will be classified and saved in both hard and soft copies for secure validation and registry procedures. Two researchers will be responsible for revision of data verification to assess the accuracy of the registered data and completing it with the postoperative data. Operative procedures: All procedures will be performed by the same surgeon using standard phacoemulsification. All patients will have immediate pre-operative limbal-corneal marking while sitting upright and looking straight ahead using the slit lamp to avoid any cyclotorsion of the eyeball which could be induced by lying supine. Clear corneal incisions group: During surgery, the Steep meridian will be identified and marked using mendez ring and marker. Additional marks will be added 20 degree away from both sides of the paired incisions for further enlargement of the wound to be 4mm. One clear corneal incision will be made on one side of the steep axis using 2.4mm keratome knife (Alcon Laboratories, Inc., Fort Worth, TX ) which is kept parallel to the iris plane to maintain an incision width of approximately 1.5 mm for secure wound sealing. Routine phacoemulsification will be performed, then intraocular lens (IOL) in the bag will be inserted. Just before irrigation/aspiration (I/A) of the ophthalmic viscoelastic, a second clear corneal incision (CCI) will be made 180 degrees from the first incision. Both incisions will be extended from both sides till reaching the marking points to be exactly 4 mm by using a keratotomy knife and checked by surgical caliper. In cases of against-the-rule (ATR) astigmatism, the opposite clear corneal incisions (OCCIs) will be made at the 3 o'clock and 9 o'clock positions. The temporal clear corneal incision will be used for phacoemulsification; the nasal CCI will not be used. In cases of with the rule astigmatism, the OCCIs will be made at the 12 o'clock and 6 o'clock positions. The superior CCI will be used for phacoemulsification; the inferior CCI will not be used. In cases of oblique astigmatism, the OCCIs will be made on the steepest meridian. The surgeon will choose the most comfortable CCI placement for phacoemulsification; the opposite symmetrical CCI will not be used. Bimanual I/A will be used in all cases. At the end of surgery, both incisions will be hydrated. Limbal relaxing incision group: The calculations of the length and position of LRI will be done using the Donnenfeld nomogram with the online calculator; http:// www.lricalculator.com. With the aid of pre-placed corneal reference marks (as done in the CCI group ), Single or paired LRI will be performed on the steep axis prior to phacoemulsification procedure using a 600 μm diamond guarded blade (Geuder LRI diamond knife, blade G-31468, Heidelberg, Germany ) and placed at least 0.5 mm anterior to the limbus. Using fixation ring, the eye will be fixated and the guarded knife is inserted at one end of the incision mark, as perpendicular to the corneal surface as possible, then advanced along the preset incision mark to complete the LRI trying at all times to maintain its perpendicular orientation. All patients had 2.4 mm clear corneal incision as the main phacoemulsification incision with no wound enlargement. Surgical induced astigmatism for the surgeon was previously calculated to be 0.5D which was used for the online LRI calculator. All patients will be prescribed antibiotic and corticosteroids eye drops. Postoperative Evaluation: Postoperative visits will be scheduled for the first postoperative day for checking of any possible complications, then at 1 week and 1, 3, 6, months after surgery. The data will be analysed using SPSS for Windows version 18.0 software (SPSS Inc., Chicago, IL, USA).The data will be shown as the mean and standard deviation. Statistical analysis will be performed using the paired-samples t test to evaluate pre-operative and post-operative data within each group such as VA, keratometry reading, astigmatism and refraction. Independent-sample t test will be used to evaluate differences in astigmatism correction between OCCI and LRI groups. Vector analysis of astigmatism correction was calculated as previously described by Alpins.

    6. Conditions and Keywords

    Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
    Corneal Astigmatism
    Keywords
    astigmatism, limbal relaxing incisions, cataract surgery

    7. Study Design

    Primary Purpose
    Treatment
    Study Phase
    Not Applicable
    Interventional Study Model
    Parallel Assignment
    Model Description
    Candidates will be randomly divided into two groups, OCCE group & LRI group before their cataract surgery.
    Masking
    Participant
    Allocation
    Randomized
    Enrollment
    120 (Anticipated)

    8. Arms, Groups, and Interventions

    Arm Title
    Clear corneal incisions
    Arm Type
    Experimental
    Arm Description
    the Steep meridian will be identified and marked, One clear corneal incision will be made on one side of the steep axis using 2.4mm keratome knife then enlarged to 4mm after completion of cataract surgery & other corneal 4mm incision is added to the other side of the steep axis
    Arm Title
    Limbal relaxing incision
    Arm Type
    Experimental
    Arm Description
    Single or paired LRI will be performed on the steep axis prior to phaco-emulsification procedure using a 600 μm diamond guarded blade.
    Intervention Type
    Procedure
    Intervention Name(s)
    surgical correction of astigmatism with cataract
    Intervention Description
    The Steep meridian will be identified and marked, relaxing limbal / corneal incisions will be designed according to it.
    Primary Outcome Measure Information:
    Title
    change of corneal astigmatism assessed by K readings measurment
    Description
    keratometry readings by autokeratometry, Topcon KR-8900, Tokyo, Japan ) confirmed by Pentacam (Sirius Scheimpflug Placido topography .CSO, Florence, Italy).
    Time Frame
    1month post operative , 3 month post operative , 6 month post operative
    Secondary Outcome Measure Information:
    Title
    change of manifest refraction assessed by autorefractometer (Topcon KR-8900, Tokyo,
    Description
    sphere & cylinder power in diopters combined to report spherical equivalent measured by autorefractometer (Topcon KR-8900, Tokyo, Japan )
    Time Frame
    1month post operative , 3 month post operative , 6 month post operative

    10. Eligibility

    Sex
    All
    Minimum Age & Unit of Time
    21 Years
    Maximum Age & Unit of Time
    80 Years
    Accepts Healthy Volunteers
    No
    Eligibility Criteria
    Inclusion Criteria: Cataract patients aged 21- 80 years. keratometric astigmatism 1D - 4D. Healthy clear cornea Exclusion Criteria: History of previous keratorefractive or anterior segment surgery. Previous ocular trauma . Corneal scar or opacities. Irregular corneal astigmatism. Cataract unsuitable for phacoemulsification. Ongoing chronic ocular pathology

    12. IPD Sharing Statement

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    Limbal Relaxing Incisions Versus Paired 4 mm Clear Corneal Incisions on Steep Meridian During Phacoemulsification

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