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Intraocular Lens Power Calculation for Combined Phaco-vitrectomy Procedures

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
 
ClinicalTrials.gov Identifier: NCT03856346
Recruitment Status : Unknown
Verified April 2019 by Josef Guber, Cantonal Hospital of St. Gallen.
Recruitment status was:  Not yet recruiting
First Posted : February 27, 2019
Last Update Posted : May 2, 2019
Sponsor:
Information provided by (Responsible Party):
Josef Guber, Cantonal Hospital of St. Gallen

Study Description
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Brief Summary:
The aim of the study is to evaluate the degree of refractive error postoperatively in combined procedures and to calculate a new constant in order to improve current state of the art biometry calculations.

Condition or disease Intervention/treatment
Intraocular Lens Calculation Combined Phaco-vitrectomy Diagnostic Test: Biometry

Detailed Description:
The IOL power calculation in combined phaco-vitrectomy has been performed similar to that in cataract surgery alone. In patients who undergo combined phaco-vitrectomy, deviations in refractive outcomes may be observed because of possible errors in measurement of axial length, changes in the properties of the vitreous cavity after removal of the vitreous, or intraocular tamponade. Most of the previous studies have reported variable degrees of myopic shift after phaco-vitrectomy for diabetic retinopathy, epiretinal membrane, and macular hole. Furthermore, use of intraoperative gas may increase further the risk of anterior displacement of the intraocular lens which may induce a higher myopic shift. However, these publications did not provide any quantification of the spherical deviations nor calculate any specific constant in order to improve currents state of art biometry calculations.
Study Design
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Study Type : Observational
Estimated Enrollment : 200 participants
Observational Model: Case-Only
Time Perspective: Prospective
Official Title: Intraocular Lens Power Calculation for Combined Phaco-vitrectomy Procedures: Calculation of a New Constant for Biometry IOL-formulas
Estimated Study Start Date : June 1, 2019
Estimated Primary Completion Date : June 30, 2020
Estimated Study Completion Date : September 30, 2020
Groups and Cohorts
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Group/Cohort Intervention/treatment
Phaco-vitrectomy Diagnostic Test: Biometry
Biometry for phaco-vitrectomy procedures pre- and postoperatively


Outcome Measures
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Primary Outcome Measures :
  1. Refractive prediction error (measured by subjective refraction, in diopters) [ Time Frame: 6 weeks postoperatively ]
    postoperative actual subjective refraction minus preoperative planned refraction in spherical equivalence (in diopters)

  2. Absolute prediction error (measured by subjective refraction, in diopters) [ Time Frame: 6 weeks postoperatively ]
    absolute value of the difference between postoperative actual refraction and preoperative planned refraction (in diopters)

  3. Changes in Axial Length (measured by biometry, in milimeters) [ Time Frame: 6 weeks postoperatively ]
    Change of axial length postoperatively (in milimeter)

  4. Changes in corneal curvature (measured by corneal topography, in diopters) [ Time Frame: 6 weeks postoperatively ]
    change in corneal curvature (in diopters)


Eligibility Criteria
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Ages Eligible for Study:   18 Years to 99 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Sampling Method:   Probability Sample
Study Population
Patients who undergo a combined procedure with phacoemulsification and pars plana vitrectomy
Criteria

Inclusion Criteria:

  • Patients who undergo a combined procedure with phacoemulsification and pars plana vitrectomy

Exclusion Criteria:

  • Sulcus fixation of the IOL, sulcus suture of the IOL, or intra-scleral IOL fixation because of intraoperative posterior capsule rupture
  • corneal disease, such as keratoconus, that interfered with refractive results
  • IOL implantation with a toric IOL or multifocal IOL
  • History of previous vitrectomy or corneal transplantation
  • Other coexisting ocular disease such as proliferative diabetic retinopathy, advanced age-related macular degeneration, uveitis, acute retinal necrosis, Coat's disease, proliferative vitreous retinopathy, or trauma
  • Intraocular tamponade using silicon oil
Contacts and Locations
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Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03856346


Contacts
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Contact: Josef Guber, MD +41 71 494 17 54 josef.guber@hotmail.com

Locations
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Switzerland
Cantonal Hospital of Sankt Gallen
Sankt Gallen, Switzerland, 9007
Sponsors and Collaborators
Cantonal Hospital of St. Gallen
More Information
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Responsible Party: Josef Guber, Consultant ophthalmic surgeon, Cantonal Hospital of St. Gallen
ClinicalTrials.gov Identifier: NCT03856346    
Other Study ID Numbers: Phaco-vity-biometry study
First Posted: February 27, 2019    Key Record Dates
Last Update Posted: May 2, 2019
Last Verified: April 2019
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No

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Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Keywords provided by Josef Guber, Cantonal Hospital of St. Gallen:
Vitrectomy
Phacoemulsification
Biometry
IOL calculation
Cataract