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

The recruitment status of this study is unknown. The completion date has passed and the status has not been verified in more than two years.
Verified July 2010 by Hospital Authority, Hong Kong.
Recruitment status was:  Active, not recruiting
Information provided by:
Hospital Authority, Hong Kong Identifier:
First received: November 21, 2007
Last updated: July 6, 2010
Last verified: July 2010
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.

Condition Intervention
Pterygium Cataract Astigmatism Procedure: pterygium excision

Study Type: Interventional
Study Design: Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Effect of Pterygium Excision on IOL Power Calculation: Concurrent Cataract and Pterygium

Resource links provided by NLM:

Further study details as provided by Hospital Authority, Hong Kong:

Primary Outcome Measures:
  • IOL power [ Time Frame: 1 and 3 months post pterygium excision ]
  • Astigmatism [ Time Frame: 1 and 3 months post pterygium excision ]

Estimated Enrollment: 40
Study Start Date: December 2003
Estimated Study Completion Date: December 2004

Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All

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.
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Please refer to this study by its identifier: NCT00563667

Alice Ho Miu Ling Nethersole Hospital
Hong Kong, China
Hong Kong Eye Hospital
Hong Kong, China
Prince of Wales Hospital
Hong Kong, China
Sponsors and Collaborators
Hospital Authority, Hong Kong
Principal Investigator: Lulu Cheng, Dr Department of DOVS, Prince of Wales Hospital/ The Chinese University of Hong Kong
  More Information

Additional Information: Identifier: NCT00563667     History of Changes
Other Study ID Numbers: CRE-2003.353
Study First Received: November 21, 2007
Last Updated: July 6, 2010

Keywords provided by Hospital Authority, Hong Kong:

Additional relevant MeSH terms:
Lens Diseases
Eye Diseases
Refractive Errors
Conjunctival Diseases processed this record on September 18, 2017