NCT00347516

Brief Summary

Implantation of an intraocular lens is the gold standard in modern day cataract surgery. The appropriate lens power needed to achieve the desired refractive outcome can be calculated with a whole variety of formulas. To date, there has been no prospective study conducted to evaluate the accuracy of the IOL power calculation formulae commonly in use. It is well established that the frequently used IOL formulas do not show significant differences when used in eyes of average axial length (i.e. between 22mm and 25mm) and it is at the extremes of axial lengths where discrepancies arise. Our aim is to find the most appropriate formula(e) for these 'long' and 'short eyes' particularly in our population where there is a significant proportion of high myopes.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
210

participants targeted

Target at P75+ for not_applicable

Timeline
Completed

Started Dec 2005

Longer than P75 for not_applicable

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

Study Start

First participant enrolled

December 1, 2005

Completed
7 months until next milestone

First Submitted

Initial submission to the registry

June 30, 2006

Completed
4 days until next milestone

First Posted

Study publicly available on registry

July 4, 2006

Completed
3.4 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

December 1, 2009

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

December 1, 2009

Completed
Last Updated

May 12, 2010

Status Verified

May 1, 2010

Enrollment Period

4 years

First QC Date

June 30, 2006

Last Update Submit

May 11, 2010

Conditions

Cataract

Keywords

IOL formulaHigh myopiaaxial length

Outcome Measures

Primary Outcomes (1)

  • Mean absolute error (MAE) which is calculated by subtracting the intended formula-derived preoperative refractive error from the actual postoperative refractive error.

Interventions

IOL calculation formulaPROCEDURE

Eligibility Criteria

Age21 Years+
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Eyes with significant cataract and suitable for phacoemulsification and primary implantation of posterior chamber intraocular lens.
  • Cataract as the only ophthalmic pathology causing significant visual impairment.
  • Axial length less than 22mm or more than 25mm, as measured by Zeiss IOL Master.
  • Evidence of a personally signed and dated informed consent document indicating the patient (or a legally acceptable representative) has been informed of all pertinent aspects of the trial.
  • Patient is willing and able to comply with scheduled visits and other study procedures.

You may not qualify if:

  • Presence of other ophthalmic pathology causing visual impairment: amblyopia, glaucoma, optic neuropathy, age related macular degeneration, macular oedema, retinal detachment, proliferative diabetic retinopathy, ocular inflammation.
  • Previous intraocular or corneal surgery (including refractive surgery).
  • Corneal opacities or irregularities: previous scarring, dystrophy, ectasia
  • Corneal astigmatism greater than 1.5 dioptres.
  • Axial length unable to be measured by the Zeiss IOL master.
  • Other ocular surgery at time of cataract extraction.
  • Uncontrolled diabetes.
  • Any neurological condition which may interfere with performance of required tests.
  • Other severe acute or chronic medical or psychiatric condition that may increase the risk associated with study participation or may interfere with the interpretation of study results.
  • The patient will not be included in the study if any of the following complications are encountered during surgery:
  • Inability to achieve secure 'in-the-bag' placement of the IOL (i.e. due to posterior capsule rupture, radial tear in capsulorhexis, vitreous loss, zonular rupture)
  • Use of corneal sutures.
  • Multiple operative procedures at the time of IOL implantation.
  • Haptic not in the capsular bag.
  • Decentration of the IOL of more than 1.0mm.
  • +1 more criteria

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Singapore National Eye Centre

Singapore, 168751, Singapore

Location

MeSH Terms

Conditions

Cataract

Condition Hierarchy (Ancestors)

Lens DiseasesEye Diseases

Study Officials

  • Zainah Alsagoff, FRCSEd

    Singapore National Eye Centre

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
SINGLE
Intervention Model
PARALLEL
Sponsor Type
OTHER GOV

Study Record Dates

First Submitted

June 30, 2006

First Posted

July 4, 2006

Study Start

December 1, 2005

Primary Completion

December 1, 2009

Study Completion

December 1, 2009

Last Updated

May 12, 2010

Record last verified: 2010-05

Locations

SG(1)