Pterygium, Cataract, Astigmatism
Conditions
Keywords
Pterygium, Cataract, Astigmatism
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.
Interventions
PROCEDUREpterygium excision
Sponsors
Hospital Authority, Hong Kong
Study design
Allocation
NON_RANDOMIZED
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
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.
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| IOL power | 1 and 3 months post pterygium excision |
| Astigmatism | 1 and 3 months post pterygium excision |
Countries
China
Outcome results
None listed