Assessing the Astigmatism Reducing Effect With Toric IOLs in Eyeswith Low Astigmatism

Sponsor
Prim. Prof. Dr. Oliver Findl, MBA (Other)
Overall Status
Unknown status
CT.gov ID
NCT03538964
Collaborator
(none)
25
1
2
27
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Study Details

Study Description

Brief Summary

Comparison of the astigmatism reducing effect of a toric IOL with a non toric IOL in eyes with low corneal astigmatism.

Condition or Disease Intervention/Treatment Phase
  • Procedure: toric intraocular lens
  • Procedure: non toric intraocular lens
N/A

Detailed Description

With increasing demands of patients concerning refractive outcome after cataract surgery, toric intraocular lenses (IOLs) that correct corneal astigmatism have been introduced more widely to cataract surgery. Originally, toric IOLs were used mainly for patients with high degrees of astigmatism. Since a couple of years, toric IOLs are available from numerous manufacturers to correct moderate amounts of astigmatism which are much more prevalent with about 8% having a corneal astigmatism of 2.0D or more in the cataract population. 5Using toric IOLs for these eyes results in less spectacle dependence of patients due to the astigmatic correction. Other astigmatism reducing techniques, such as peripheral corneal relaxing incisions and opposite clear corneal incisions were shown to be less predictable. Although the use of toric IOLs became the gold standard to correct corneal astigmatism during cataract surgery , there is still uncertainty, if low astigmatism should be corrected. Visser et al. showed that moderate astigmatism of than 1.5D should be corrected for monofocal IOLs and Hayashi showed that remaining astigmatism of 1.0D already decreases visual quality in eyes with multifocal IOLs. Although correction of low corneal astigmatism appears to be beneficial, some hurdles have to be taken into account. In eyes with low corneal astigmatism the accuracy of measuring the astigmatism meridian is relatively low. Furthermore, different corneal measurement techniques are not always comparable and it is difficult to know, which device shows the correct amount of astigmatism. Additionally, the correction of the spherical equivalent is of high importance, as a refractive surprise will also attenuate the astigmatism reducing effect of the toric IOL. Aim of this study is to assess, if toric IOLs are useful in patients with low amounts of corneal astigmatism and to quantify the sources of error in toric IOL power calculation.

Study Design

Study Type:
Interventional
Anticipated Enrollment :
25 participants
Allocation:
Randomized
Intervention Model:
Parallel Assignment
Masking:
None (Open Label)
Primary Purpose:
Treatment
Official Title:
Assessing the Astigmatism Reducing Effect With Toric IOLs in Eyeswith Low Astigmatism
Actual Study Start Date :
May 2, 2018
Anticipated Primary Completion Date :
May 2, 2020
Anticipated Study Completion Date :
Aug 1, 2020

Arms and Interventions

Arm Intervention/Treatment
Active Comparator: Toric intraocular lens (IOL)

toric intraocular lens for low astigmatism correction

Procedure: toric intraocular lens
cataract surgery with implantation of an toric intraocular lens

Sham Comparator: Non toric intraocular lens (IOL)

non toric intraocular lens

Procedure: non toric intraocular lens
cataract surgery with implantation of a non toric intraocular lens

Outcome Measures

Primary Outcome Measures

  1. Subjective refraction to detect remaining astigmatism (in Diopters) between both groups [12 months]

Secondary Outcome Measures

  1. Biometrical measurement of axial length (in mm), anterior chamber depth (in mm), corneal astigmatism (radii and axial degrees) [12 months]

  2. Purkinjemeter measurement of Tilt (in degrees) and Decentration (in degrees) of the intraocular lens [12 months]

  3. Wavefront analysis of high order aberrations (root mean square, in microns) [12 months]

  4. Questionnaire to asses patients subjective satisfaction with visual outcome [12 months]

    In the questionnaire the patient has to choose if different tasks (e.g. reading, driving, watching TV) are easier for him/ her with the right eye, the left eye, or if there is no difference between both eyes

Eligibility Criteria

Criteria

Ages Eligible for Study:
21 Years to 100 Years
Sexes Eligible for Study:
All
Accepts Healthy Volunteers:
No
Inclusion Criteria:
  • cataract

  • Age 21 and older

  • Regular corneal astigmatism 0.5D up to 1.5 D and difference between eyes not more than 0.75D

  • written informed consent prior to surgery

Exclusion Criteria:
  • relevant other ophthalmic diseases such as: pseudoexfoliation, glaucoma, traumatic cataract corneal scars, and other co-morbidity that could affect capsule bag stability ( e.g. Marfan syndrome)

  • Irregular corneal astigmatism on corneal topography

  • In case of pregnancy (pregnancy test will be taken preoperatively in women of reproductive age)

Contacts and Locations

Locations

Site City State Country Postal Code
1 Vienna Institute for Research in Ocular Surgery (VIROS) Vienna Austria 1140

Sponsors and Collaborators

  • Prim. Prof. Dr. Oliver Findl, MBA

Investigators

None specified.

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.
Responsible Party:
Prim. Prof. Dr. Oliver Findl, MBA, Principal Investigator, Vienna Institute for Research in Ocular Surgery
ClinicalTrials.gov Identifier:
NCT03538964
Other Study ID Numbers:
  • Low Asti
First Posted:
May 29, 2018
Last Update Posted:
Oct 2, 2019
Last Verified:
Oct 1, 2019
Individual Participant Data (IPD) Sharing Statement:
Undecided
Plan to Share IPD:
Undecided
Studies a U.S. FDA-regulated Drug Product:
No
Studies a U.S. FDA-regulated Device Product:
No
Keywords provided by Prim. Prof. Dr. Oliver Findl, MBA, Principal Investigator, Vienna Institute for Research in Ocular Surgery
Additional relevant MeSH terms:

Study Results

No Results Posted as of Oct 2, 2019