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

Not Applicable

• Conditions: Pterygium; Cataract; Astigmatism

• Registration Number: NCT00563667
• Lead Sponsor: Hospital Authority, Hong Kong

Brief Summary

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.

Detailed Description

Not available

Study Timeline

• Study Start: 2003-12
• Study Completion: 2004-12
• Study First Submitted: 2007-11-21
• Study First Submitted QC: 2007-11-23
• Study First Posted: 2007-11-26
• Status Verified: 2010-07
• Last Update Submitted: 2010-07-06
• Last Update Posted: 2010-07-07

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 40

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.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Primary Outcome Measures

Name	Time	Method
IOL power	1 and 3 months post pterygium excision
Astigmatism	1 and 3 months post pterygium excision

Trial Locations

Locations (3)

Alice Ho Miu Ling Nethersole Hospital; 🇨🇳 Hong Kong, China

Hong Kong Eye Hospital; 🇨🇳 Hong Kong, China

Prince of Wales Hospital; 🇨🇳 Hong Kong, China