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
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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Layout table for eligibility information
Ages Eligible for Study:
18 Years and older (Adult, Older Adult)
Sexes Eligible for Study:
All cases with concomitant cataract and primary pterygium, which are indicated for surgery.
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.