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Effect of Pterygium Excision on Intraocular Lens Power Calculation for Subsequent Cataract Operation

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ClinicalTrials.gov Identifier: NCT00563667
Recruitment Status : Unknown
Verified July 2010 by Hospital Authority, Hong Kong.
Recruitment status was:  Active, not recruiting
First Posted : November 26, 2007
Last Update Posted : July 7, 2010
Information provided by:

November 21, 2007
November 26, 2007
July 7, 2010
December 2003
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  • IOL power [ Time Frame: 1 and 3 months post pterygium excision ]
  • Astigmatism [ Time Frame: 1 and 3 months post pterygium excision ]
Same as current
Complete list of historical versions of study NCT00563667 on ClinicalTrials.gov Archive Site
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Effect of Pterygium Excision on Intraocular Lens Power Calculation for Subsequent Cataract Operation
Effect of Pterygium Excision on IOL Power Calculation: Concurrent Cataract and Pterygium
Pterygium is known to induce with-the-rule astigmatism. Excision of pterygium will steepen the cornea and reduce corneal astigmatism. We postulate that the alteration of keratometry reading will indirectly affect the IOL power calculation in cases with concurrent pterygium and cataract. Concurrent pterygium and cataract is common in Hong Kong and other tropical regions. The effect of pterygium excision on intraocular lens power calculation is investigated.
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Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
  • Pterygium
  • Cataract
  • Astigmatism
Procedure: pterygium excision
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*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
Unknown status
December 2004
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Inclusion Criteria:

  • All cases with concomitant cataract and primary pterygium, which are indicated for surgery.

Exclusion Criteria:

  • Pterygium smaller than 1mm, which is not visually significant.
  • Double headed pterygium
  • Pterygium obscuring visual axis that preclude keratometry or autorefraction measurements.
  • Previous corneal refractive surgery that alter the keratometric power of the cornea.
  • Patients with medical problems that preclude staged ocular surgery, e.g. dementia, heart disease, on warfarin.
Sexes Eligible for Study: All
18 Years and older   (Adult, Senior)
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Contact information is only displayed when the study is recruiting subjects
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Hospital Authority, Hong Kong
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Principal Investigator: Lulu Cheng, Dr Department of DOVS, Prince of Wales Hospital/ The Chinese University of Hong Kong
Hospital Authority, Hong Kong
July 2010

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP